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Question 1 of 20
1. Question
Consider the following:
1. By cutting a spring into two equal halves, the stiffness of each part reduces to half.
2. By adding a new spring of equal stiffness in parallel, the stiffness of the new arrangement also doubles.
Which of the above statements is/are correct?Correct
Answer: A
Explanation:
Spring stiffness: A stiff spring requires more force to compress or stretch than a soft spring with lower stiffness. Thus, spring stiffness determines how much the spring will deform under a given load. Spring length, wire diameter, and number of coils are all important factors that affect spring stiffness. Spring rate or spring constant is a physical quantity which determines the spring stiffness. The higher the spring constant, more is the spring stiffness.
• Statement 1 is INCORRECT: By cutting a spring in half doubles the spring constant. This arrangement is known as spring in series.
• Statement 2 is CORRECT: By adding a new spring of equal stiffness, the forces produced by the springs add together. Therefore, it can be stated that the spring constants add together and become double. This is a parallel arrangement.Incorrect
Answer: A
Explanation:
Spring stiffness: A stiff spring requires more force to compress or stretch than a soft spring with lower stiffness. Thus, spring stiffness determines how much the spring will deform under a given load. Spring length, wire diameter, and number of coils are all important factors that affect spring stiffness. Spring rate or spring constant is a physical quantity which determines the spring stiffness. The higher the spring constant, more is the spring stiffness.
• Statement 1 is INCORRECT: By cutting a spring in half doubles the spring constant. This arrangement is known as spring in series.
• Statement 2 is CORRECT: By adding a new spring of equal stiffness, the forces produced by the springs add together. Therefore, it can be stated that the spring constants add together and become double. This is a parallel arrangement. -
Question 2 of 20
2. Question
Consider the following statements:
1. Diffraction happens when waves emerge from two different sources, producing different wave front.
2. Interference occurs due to secondary waves that emerge from different parts of the same wave.
Which of the above statements is/are correct?Correct
Answer: D
Explanation:
Diffraction
The phenomenon in which light bends around the corner of the particles spreading into different regions of the geometrical shadow of the aperture is called Diffraction.
Interference
The phenomenon in which two waves travelling in the same direction in the same medium superpose on each other, resulting in different wave fronts is called Interference.
• Statement 1 is INCORRECT: Interference may be defined as waves emerging from two different sources, producing different wave fronts.
• Statement 2 is INCORRECT: Diffraction occurs as secondary waves that emerge from the different parts of the same wave.Incorrect
Answer: D
Explanation:
Diffraction
The phenomenon in which light bends around the corner of the particles spreading into different regions of the geometrical shadow of the aperture is called Diffraction.
Interference
The phenomenon in which two waves travelling in the same direction in the same medium superpose on each other, resulting in different wave fronts is called Interference.
• Statement 1 is INCORRECT: Interference may be defined as waves emerging from two different sources, producing different wave fronts.
• Statement 2 is INCORRECT: Diffraction occurs as secondary waves that emerge from the different parts of the same wave. -
Question 3 of 20
3. Question
Consider the following cases:
1. Detection of cracks in metal blocks
2. Detection of earthquake waves.
3. Cleaning of dust and grease on objects.
In how many of the above-mentioned cases ultrasonic waves are used?Correct
Answer: B
Explanation:
Infrasound: Sounds of frequencies below 20 Hz are called infrasonic sound or infrasound.
Ultrasound: Frequencies higher than 20 kHz are called ultrasonic sound or ultrasound.
• Case 1 is CORRECT: Ultrasonic waves are passed through the metal block and detectors are used to detect the transmitted waves. If there is even a small crack, the ultrasound gets reflected back indicating the presence of flaw or defect.
• Case 2 is INCORRECT: Infrasonic waves are for monitoring earthquakes and volcanoes, charting rock and petroleum formations below the earth and other applications to study the mechanics of the earth.
• Case 3 is CORRECT: Ultrasonic waves are used to clean dirt and grease. The high frequency wave causes the particle to get detached from the surface of the object and thus, the object gets thoroughly cleaned.Incorrect
Answer: B
Explanation:
Infrasound: Sounds of frequencies below 20 Hz are called infrasonic sound or infrasound.
Ultrasound: Frequencies higher than 20 kHz are called ultrasonic sound or ultrasound.
• Case 1 is CORRECT: Ultrasonic waves are passed through the metal block and detectors are used to detect the transmitted waves. If there is even a small crack, the ultrasound gets reflected back indicating the presence of flaw or defect.
• Case 2 is INCORRECT: Infrasonic waves are for monitoring earthquakes and volcanoes, charting rock and petroleum formations below the earth and other applications to study the mechanics of the earth.
• Case 3 is CORRECT: Ultrasonic waves are used to clean dirt and grease. The high frequency wave causes the particle to get detached from the surface of the object and thus, the object gets thoroughly cleaned. -
Question 4 of 20
4. Question
Consider the following cases:
1. Speed of a moving vehicle.
2. Depth of a sea.
3. Gap between two houses.
In how many of the above-mentioned cases, Doppler Effect can be used to determine the value?Correct
Answer: A
Explanation:
Doppler Effect refers to the change in wave frequency during the relative motion between a wave source and its observer. It is to be noted that this property can be used only if there is relative speed between wave source and observer.
• Case 1 is CORRECT: Since the vehicle is moving. So, there is a relative speed between the observer and source. Doppler Effect can be used to determine the speed of a moving vehicle.
• Case 2 is INCORRECT: Doppler Effect is used to track speed of submarines. But, it is SONAR (Sound Navigation and Ranging) which works on the principle of echo, which is used to measure the depth of a sea.
• Case 3 is INCORRECT: Since houses are stationary, Doppler Effect cannot be used directly to measure the gap between two houses.Incorrect
Answer: A
Explanation:
Doppler Effect refers to the change in wave frequency during the relative motion between a wave source and its observer. It is to be noted that this property can be used only if there is relative speed between wave source and observer.
• Case 1 is CORRECT: Since the vehicle is moving. So, there is a relative speed between the observer and source. Doppler Effect can be used to determine the speed of a moving vehicle.
• Case 2 is INCORRECT: Doppler Effect is used to track speed of submarines. But, it is SONAR (Sound Navigation and Ranging) which works on the principle of echo, which is used to measure the depth of a sea.
• Case 3 is INCORRECT: Since houses are stationary, Doppler Effect cannot be used directly to measure the gap between two houses. -
Question 5 of 20
5. Question
Consider the following devices:
1. Mobile charger
2. Inverter at home
3. Laptop Adapter
How many of the above-mentioned devices convert Alternating Current (AC) to Direct Current (DC)?Correct
Answer: B
Explanation:
• 1st device is CORRECT: A mobile phone works on a Lithium Ion battery. Rectifier is an electrical device which is embedded in a mobile charger which converts DC to AC. Thus, mobile charger as a whole converts AC to DC.
• 2nd device is INCORRECT: Inverter at home basically converts DC into AC. It converts direct current, which is produced by a battery, into alternating current. This is needed because household electrical appliances and devices work on alternating current.
• 3rd device is CORRECT: Laptop adapter works on the same principle as mobile charger. Only difference is the voltage in operation. A mobile charger reduces voltage from 220 volts to 5 volts whereas; laptop adapter generally reduces the voltage to 12 volts.Incorrect
Answer: B
Explanation:
• 1st device is CORRECT: A mobile phone works on a Lithium Ion battery. Rectifier is an electrical device which is embedded in a mobile charger which converts DC to AC. Thus, mobile charger as a whole converts AC to DC.
• 2nd device is INCORRECT: Inverter at home basically converts DC into AC. It converts direct current, which is produced by a battery, into alternating current. This is needed because household electrical appliances and devices work on alternating current.
• 3rd device is CORRECT: Laptop adapter works on the same principle as mobile charger. Only difference is the voltage in operation. A mobile charger reduces voltage from 220 volts to 5 volts whereas; laptop adapter generally reduces the voltage to 12 volts. -
Question 6 of 20
6. Question
With reference to Hydrogenation of oil, consider the following statements:
1. It converts saturated form of oil into its unsaturated form.
2. It changes the solid state of the oil into its liquid state.
3. It increases the shelf life of the oil.
How many of the above statements are correct?Correct
Answer: A
Explanation:
Hydrogenation is a process that reduces unsaturated fatty acid content of triglycerides by attaching hydrogen atoms at the point of unsaturation.
CH2=CH2 + H2 → CH3-CH3
(Ethene) (Hydrogen) (Ethane)• Statement 1 is INCORRECT: By process of hydrogenation, unsaturated bonds (double or triple bonds) of the carbon atom are converted into their saturated form (single bond) by passing hydrogen gas through the oil in the presence of nickel as a catalyst.
• Statement 2 is INCORRECT: The chemical process of hydrogenation transforms liquid vegetable oil into solid fat. Groundnut oil, cotton oil, and mustard oil are examples of unsaturated molecules with double bonds. At room temperature, they are in a liquid condition. Vegetable oils, undergo hydrogen addition to generate a saturated product called vegetable ghee or vanaspati ghee, which is solid or semi-solid at room temperature due to the presence of single bonds.
• Statement 3 is CORRECT: Hydrogenation process increases the shelf life of the oil as it resists the oxidation of oil which prevents rancidity and bad smell.Incorrect
Answer: A
Explanation:
Hydrogenation is a process that reduces unsaturated fatty acid content of triglycerides by attaching hydrogen atoms at the point of unsaturation.
CH2=CH2 + H2 → CH3-CH3
(Ethene) (Hydrogen) (Ethane)• Statement 1 is INCORRECT: By process of hydrogenation, unsaturated bonds (double or triple bonds) of the carbon atom are converted into their saturated form (single bond) by passing hydrogen gas through the oil in the presence of nickel as a catalyst.
• Statement 2 is INCORRECT: The chemical process of hydrogenation transforms liquid vegetable oil into solid fat. Groundnut oil, cotton oil, and mustard oil are examples of unsaturated molecules with double bonds. At room temperature, they are in a liquid condition. Vegetable oils, undergo hydrogen addition to generate a saturated product called vegetable ghee or vanaspati ghee, which is solid or semi-solid at room temperature due to the presence of single bonds.
• Statement 3 is CORRECT: Hydrogenation process increases the shelf life of the oil as it resists the oxidation of oil which prevents rancidity and bad smell. -
Question 7 of 20
7. Question
Consider the following statements:
1. In the hypotonic solution, the animal cell is likely to shrink.
2. In the hypertonic solution, the medium has a higher concentration of water than the animal cell which is kept in it.
Which of the statements given above is/are NOT correct?Correct
Answer: C
Explanation:
Movement of water across a selectively permeable membrane is known as osmosis. This movement of water across the plasma membrane is also affected by the amount of substance dissolved in water or concentration of the solution.
Based on this, there are 3 types of solution.
1. Hypotonic solution
2. Isotonic solution
3. Hypertonic solution
• Statement 1 is INCORRECT: If the medium surrounding the cell has a higher water concentration than the cell, meaning that the outside solution is very dilute, the cell will gain water by osmosis. Such a solution is known as a hypotonic solution. In this, the animal cell is likely to swell up.
• Statement 2 is INCORRECT: If the medium has a lower concentration of water than the cell, meaning that it is a very concentrated solution, the cell will lose water by osmosis. Such a solution is known as a hypertonic solution.Incorrect
Answer: C
Explanation:
Movement of water across a selectively permeable membrane is known as osmosis. This movement of water across the plasma membrane is also affected by the amount of substance dissolved in water or concentration of the solution.
Based on this, there are 3 types of solution.
1. Hypotonic solution
2. Isotonic solution
3. Hypertonic solution
• Statement 1 is INCORRECT: If the medium surrounding the cell has a higher water concentration than the cell, meaning that the outside solution is very dilute, the cell will gain water by osmosis. Such a solution is known as a hypotonic solution. In this, the animal cell is likely to swell up.
• Statement 2 is INCORRECT: If the medium has a lower concentration of water than the cell, meaning that it is a very concentrated solution, the cell will lose water by osmosis. Such a solution is known as a hypertonic solution. -
Question 8 of 20
8. Question
With reference to the cell wall, consider the following statements:
1. Cell Wall is a non-permeable membrane.
2. It is made up of cellulose in plant cell.
3. It is only present in the plants.
How many of the above statements are correct?Correct
Answer: A
Explanation:
A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection.
• Statement 1 is INCORRECT: The cell wall is freely permeable as it allows water and nutrients freely exchanged between the cells and outer environment. It has a mesh like structure.
• Statement 2 is CORRECT: Cell wall of a plant cell is composed of cellulose, a glucose-based polysaccharide macromolecule.
• Statement 3 is INCORRECT: Cell wall is not only present in plants but also in fungi. The cell wall of fungi is composed mainly of glycoproteins. As the components of the fungal cell wall are not present in humans, this structure is an excellent target for antifungal therapy.Incorrect
Answer: A
Explanation:
A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection.
• Statement 1 is INCORRECT: The cell wall is freely permeable as it allows water and nutrients freely exchanged between the cells and outer environment. It has a mesh like structure.
• Statement 2 is CORRECT: Cell wall of a plant cell is composed of cellulose, a glucose-based polysaccharide macromolecule.
• Statement 3 is INCORRECT: Cell wall is not only present in plants but also in fungi. The cell wall of fungi is composed mainly of glycoproteins. As the components of the fungal cell wall are not present in humans, this structure is an excellent target for antifungal therapy. -
Question 9 of 20
9. Question
With reference to the cell organelles and their respective functions, consider the following pairs:
Cell organelles – Functions
1. Ribosomes – Protein synthesis
2. Lysosomes – Digestion of waste materials.
3. Vacuoles – Excretion of waste
How many of the above statements are correctly matched?Correct
Answer: C
Explanation:
Cell Organelles
The cell contains different functional structures which are collectively called organelles, and they are involved in various cellular functions. Some of the Large and complex cells, including cells from multicellular organisms, need a lot of chemical activities to support their complicated structure and function. To keep these activities of different kinds, separate from each other, these cells use membrane-bound little structures within themselves.
• Pair 1 is CORRECT: Ribosomes are non-membrane bound and important cytoplasmic organelles found in close association with the endoplasmic reticulum. The primary function of the ribosomes includes protein synthesis in all living cells that ensure the survival of the cell.
• Pair 2 is CORRECT: Lysosomes are membranous organelles whose specific function is to breakdown cellular wastes and debris by engulfing it.
• Pair 3 is CORRECT: A vacuole stores salts, minerals, pigments and proteins within the cell. However, in some unicellular organisms, specialised vacuoles also play important roles in expelling excess water and some wastes from the cell.Incorrect
Answer: C
Explanation:
Cell Organelles
The cell contains different functional structures which are collectively called organelles, and they are involved in various cellular functions. Some of the Large and complex cells, including cells from multicellular organisms, need a lot of chemical activities to support their complicated structure and function. To keep these activities of different kinds, separate from each other, these cells use membrane-bound little structures within themselves.
• Pair 1 is CORRECT: Ribosomes are non-membrane bound and important cytoplasmic organelles found in close association with the endoplasmic reticulum. The primary function of the ribosomes includes protein synthesis in all living cells that ensure the survival of the cell.
• Pair 2 is CORRECT: Lysosomes are membranous organelles whose specific function is to breakdown cellular wastes and debris by engulfing it.
• Pair 3 is CORRECT: A vacuole stores salts, minerals, pigments and proteins within the cell. However, in some unicellular organisms, specialised vacuoles also play important roles in expelling excess water and some wastes from the cell. -
Question 10 of 20
10. Question
With reference to cell division, consider the following statements:
1. Mitosis is a somatic cell division whereas Meiosis is a germ cell division.
2. Mitosis is a reduced division whereas Meiosis is an equated division.
Which of the statements given above is/are correct?Correct
Answer: A
Explanation:
Cell division happens when a parent cell divides into two or more cells called daughter cells. Cell division usually occurs as part of a larger cell cycle. All cells reproduce by splitting into two, where each parental cell gives rise to two daughter cells.
There are two main types of cell division in an organism – Mitosis and Meiosis
Mitosis: The process cells use to make exact replicas of themselves. Mitosis is observed in almost all the body’s cells, including eyes, skin, hair, and muscle cells.
Meiosis: In this type of cell division, sperm or egg cells are produced instead of identical daughter cells as in mitosis.
• Statement 1 is CORRECT: Mitosis is a somatic cell division. Somatic cells are all the cells except the germ cells – sperm and egg cell.
• Statement 2 is INCORRECT: Mitosis is an equated division of cells because each cell divides equally into two daughter cells and same number of chromosomes are transferred from parent to daughter cells, so it is known as equated division. But in case of Meiosis, only half of the number of chromosomes are transferred to each daughter cell. That is why, it is known as reduced division.Incorrect
Answer: A
Explanation:
Cell division happens when a parent cell divides into two or more cells called daughter cells. Cell division usually occurs as part of a larger cell cycle. All cells reproduce by splitting into two, where each parental cell gives rise to two daughter cells.
There are two main types of cell division in an organism – Mitosis and Meiosis
Mitosis: The process cells use to make exact replicas of themselves. Mitosis is observed in almost all the body’s cells, including eyes, skin, hair, and muscle cells.
Meiosis: In this type of cell division, sperm or egg cells are produced instead of identical daughter cells as in mitosis.
• Statement 1 is CORRECT: Mitosis is a somatic cell division. Somatic cells are all the cells except the germ cells – sperm and egg cell.
• Statement 2 is INCORRECT: Mitosis is an equated division of cells because each cell divides equally into two daughter cells and same number of chromosomes are transferred from parent to daughter cells, so it is known as equated division. But in case of Meiosis, only half of the number of chromosomes are transferred to each daughter cell. That is why, it is known as reduced division. -
Question 11 of 20
11. Question
Consider the following statements:
Statement I: Long distance transmission of electricity requires step up transformers.
Statement II: Step up transformers increase the current and decrease the voltage to minimise losses due to transmission.
Which one of the following is correct in respect of the above statements?Correct
Answer: C
Explanation:
Alternating current is used to transmit electricity over a very long distance. For this transformer is used to increase or decrease the voltage of transmission.
• Statement 1 is CORRECT: Step up transformer increase the voltage to very high value like 33 kilovolts (KVs) and this way current is reduced to minimise losses.
• Statement 2 is INCORRECT: Step up transformers increase the voltage and decrease the current to minimise transmission loss.Incorrect
Answer: C
Explanation:
Alternating current is used to transmit electricity over a very long distance. For this transformer is used to increase or decrease the voltage of transmission.
• Statement 1 is CORRECT: Step up transformer increase the voltage to very high value like 33 kilovolts (KVs) and this way current is reduced to minimise losses.
• Statement 2 is INCORRECT: Step up transformers increase the voltage and decrease the current to minimise transmission loss. -
Question 12 of 20
12. Question
Consider the following statements:
1. Convex mirror is used in solar cookers to concentrate sunlight.
2. Concave mirror is used as shaving mirror.
Which of the statements given above is/are correct?Correct
Answer: B
Explanation:
A spherical mirror is a mirror that has the shape of a piece cut out of a spherical surface. There are two types of spherical mirrors: concave mirror and convex mirror.
• Statement 1 is INCORRECT: Concave mirror is used in solar cookers. The reason behind using this mirror is because concave mirrors reflect light falling on it to a single focal point. This increases the heat at the focal point. This way food is cooked.
• Statement 2 is CORRECT: Concave mirror is used as shaving mirror. This is because when the face is placed close to a concave mirror, within the focus of the mirror, it produces a magnified and erect image of the face. Since an enlarged or magnified image of the face can be seen in the concave mirror, it becomes easier to make a smooth shave.
Applications of Concave Mirrors
• Shaving mirror
• Head mirrors.
• Ophthalmoscope.
• Astronomical telescopes.
• Headlights.
• Solar furnaces.
Applications of Convex Mirrors
• Rear view mirrors
• In ATMs for security purposes
• In reflector lightsIncorrect
Answer: B
Explanation:
A spherical mirror is a mirror that has the shape of a piece cut out of a spherical surface. There are two types of spherical mirrors: concave mirror and convex mirror.
• Statement 1 is INCORRECT: Concave mirror is used in solar cookers. The reason behind using this mirror is because concave mirrors reflect light falling on it to a single focal point. This increases the heat at the focal point. This way food is cooked.
• Statement 2 is CORRECT: Concave mirror is used as shaving mirror. This is because when the face is placed close to a concave mirror, within the focus of the mirror, it produces a magnified and erect image of the face. Since an enlarged or magnified image of the face can be seen in the concave mirror, it becomes easier to make a smooth shave.
Applications of Concave Mirrors
• Shaving mirror
• Head mirrors.
• Ophthalmoscope.
• Astronomical telescopes.
• Headlights.
• Solar furnaces.
Applications of Convex Mirrors
• Rear view mirrors
• In ATMs for security purposes
• In reflector lights -
Question 13 of 20
13. Question
Consider the following examples:
1. Formation of mirage in desert.
2. Sparkling of diamond
3. Blue colour of the sky
4. Transmission of data in optical fibre
Total Internal Reflection (TIR) is the guiding principle of how many of the above examples?Correct
Answer: C
Explanation:
Total Internal Reflection.
It is a complete reflection of a ray of light within a medium such as water or glass from the surrounding surfaces back into the medium. The phenomenon occurs if the angle of incidence is greater than a certain limiting angle, called the critical angle.
• Example 1 is CORRECT: A mirage is an optical phenomenon that creates the illusion of water and results from the refraction of light through a non-uniform medium. Mirages occur on sunny days. The role of the sun is to heat the roadway to high temperatures. This heated roadway in turn heats the surrounding air, keeping the air just above the roadway at higher temperatures than that day’s average air temperature. Hot air tends to be less optically dense than cooler air. This causes total internal reflection and creates an illusion of water.
• Example 2 is CORRECT: The faces of the diamond are so cut that the light entering the crystal suffers total internal reflection repeatedly and hence gets collected inside but it comes out only through a few faces. Hence the diamond sparkles when seen in the direction of emerging light.
• Example 3 is INCORRECT: Blue colour of the sky is due to scattering of light. The two most common types of matter present in the atmosphere are gaseous nitrogen and oxygen. These particles are most effective in scattering the higher frequency and shorter wavelength portions of the visible light spectrum.
• Example 4 is CORRECT: In optical fibres, propagation of light takes place due to total internal reflection. When light falls one end of the optical fibre; it gets refracted into the fibre. The refracted ray of light falls on the interface separating the fibre and coating an angle which is greater than the critical angle. Thus, the TIR can take place. The light travels the entire length of the fibre and arrives at other ends of the fibre without any loss in its intensity even if the fibre is rounded and curved.
Incorrect
Answer: C
Explanation:
Total Internal Reflection.
It is a complete reflection of a ray of light within a medium such as water or glass from the surrounding surfaces back into the medium. The phenomenon occurs if the angle of incidence is greater than a certain limiting angle, called the critical angle.
• Example 1 is CORRECT: A mirage is an optical phenomenon that creates the illusion of water and results from the refraction of light through a non-uniform medium. Mirages occur on sunny days. The role of the sun is to heat the roadway to high temperatures. This heated roadway in turn heats the surrounding air, keeping the air just above the roadway at higher temperatures than that day’s average air temperature. Hot air tends to be less optically dense than cooler air. This causes total internal reflection and creates an illusion of water.
• Example 2 is CORRECT: The faces of the diamond are so cut that the light entering the crystal suffers total internal reflection repeatedly and hence gets collected inside but it comes out only through a few faces. Hence the diamond sparkles when seen in the direction of emerging light.
• Example 3 is INCORRECT: Blue colour of the sky is due to scattering of light. The two most common types of matter present in the atmosphere are gaseous nitrogen and oxygen. These particles are most effective in scattering the higher frequency and shorter wavelength portions of the visible light spectrum.
• Example 4 is CORRECT: In optical fibres, propagation of light takes place due to total internal reflection. When light falls one end of the optical fibre; it gets refracted into the fibre. The refracted ray of light falls on the interface separating the fibre and coating an angle which is greater than the critical angle. Thus, the TIR can take place. The light travels the entire length of the fibre and arrives at other ends of the fibre without any loss in its intensity even if the fibre is rounded and curved.
-
Question 14 of 20
14. Question
Consider the following statements:
1. North Pole of the Earth’s magnetic field and the Earth’s geographical North Pole lie in opposite direction.
2. Aurora Borealis is visible due to Earth’s magnetic field.
3. Magnetic force of the Earth is stronger than its gravitational force.
How many of the above statements are correct?Correct
Answer: B
Explanation:
• Statement 1 is CORRECT: North Pole of the Earth’s magnetic field and the Earth’s geographic poles are opposite. Earth’s geographic and magnetic poles do not have the same polarity because they arise from different mechanisms. Earth’s magnetic field is caused by circulating currents of liquid iron in the outer core. Furthermore, earth’s magnetic poles are constantly changing location relative to earth’s geographic poles. Currently, the magnetic south pole lies about ten degrees distant from the geographic north pole and sits in the Arctic Ocean north of Alaska. The north end on a compass therefore currently points roughly towards Alaska and not exactly towards geographic north.
• Statement 2 is CORRECT: Aurora Borealis or the Northern Lights are magnificent display of light due to earth’s magnetic field. The solar discharge enters earth’s atmosphere. These ionised particles interact with gases in our atmosphere resulting in beautiful displays of light in the sky. Oxygen gives off green and red light. Nitrogen glows blue and purple.
• Statement 3 is INCORRECT: Earth’s gravitational force is way stronger than earth’s magnetic force. Because even a small particle gets attracted towards centre of earth due to force of gravity. But, magnetic force does not pull all the magnetic substance towards either of the poles.Incorrect
Answer: B
Explanation:
• Statement 1 is CORRECT: North Pole of the Earth’s magnetic field and the Earth’s geographic poles are opposite. Earth’s geographic and magnetic poles do not have the same polarity because they arise from different mechanisms. Earth’s magnetic field is caused by circulating currents of liquid iron in the outer core. Furthermore, earth’s magnetic poles are constantly changing location relative to earth’s geographic poles. Currently, the magnetic south pole lies about ten degrees distant from the geographic north pole and sits in the Arctic Ocean north of Alaska. The north end on a compass therefore currently points roughly towards Alaska and not exactly towards geographic north.
• Statement 2 is CORRECT: Aurora Borealis or the Northern Lights are magnificent display of light due to earth’s magnetic field. The solar discharge enters earth’s atmosphere. These ionised particles interact with gases in our atmosphere resulting in beautiful displays of light in the sky. Oxygen gives off green and red light. Nitrogen glows blue and purple.
• Statement 3 is INCORRECT: Earth’s gravitational force is way stronger than earth’s magnetic force. Because even a small particle gets attracted towards centre of earth due to force of gravity. But, magnetic force does not pull all the magnetic substance towards either of the poles. -
Question 15 of 20
15. Question
Consider the following pairs:
Materials – Magnetic Action
1. Ferromagnetic materials – strongly attracted by magnets
2. Diamagnetic materials – weakly attracted by magnets.
3. Paramagnetic materials – weakly repelled by magnets.
How many of the above pairs are correctly matched?Correct
Answer: A
Explanation:
• Pair 1 is CORRECT: Ferromagnetic materials exhibit a strong attraction towards magnets. They don’t necessarily produce their own magnetic field; only magnets produce a magnetic field. Ferromagnetic materials simply pull themselves towards magnets. They have a strong attraction towards magnets.
• Pair 2 is INCORRECT: Diamagnetic materials are those that repel magnets. They don’t exhibit any attraction to magnets. Rather, diamagnetic materials exhibit the opposite behaviour i.e. they repel magnets.
• Pair 3 is INCORRECT: Paramagnetic materials exhibit a weak attraction towards magnets. They still pull themselves towards magnets, but paramagnetic materials are much weaker than ferromagnetic materials.Incorrect
Answer: A
Explanation:
• Pair 1 is CORRECT: Ferromagnetic materials exhibit a strong attraction towards magnets. They don’t necessarily produce their own magnetic field; only magnets produce a magnetic field. Ferromagnetic materials simply pull themselves towards magnets. They have a strong attraction towards magnets.
• Pair 2 is INCORRECT: Diamagnetic materials are those that repel magnets. They don’t exhibit any attraction to magnets. Rather, diamagnetic materials exhibit the opposite behaviour i.e. they repel magnets.
• Pair 3 is INCORRECT: Paramagnetic materials exhibit a weak attraction towards magnets. They still pull themselves towards magnets, but paramagnetic materials are much weaker than ferromagnetic materials. -
Question 16 of 20
16. Question
Consider the following statements:
Statement I: Tissues are only found in multicellular organisms.
Statement II: Tissues carry out specialised functions.
Which one of the following is correct in respect of the above statements?Correct
Answer: A
Explanation:
The cells in complex multicellular organisms, like human beings, are organized into tissues, which are groups of similar cells that work together on a specific task.
• Both Statements are CORRECT and Statement 2 is the CORRECT explanation of Statement 1.
• Statement 1 is CORRECT: Tissues are only found in Multicellular organisms. Since, multicellular organisms have complex biological tasks which are performed by specialised groups of cells. In unicellular organisms, all the functions like ingestion, digestion, locomotion etc is performed by a single cell.
• Statement 2 is CORRECT and is the CORRECT explanation of statement 1: For efficient functioning of organs and organ system in a multicellular organism. Some of the common tissues are blood, muscles etc.Incorrect
Answer: A
Explanation:
The cells in complex multicellular organisms, like human beings, are organized into tissues, which are groups of similar cells that work together on a specific task.
• Both Statements are CORRECT and Statement 2 is the CORRECT explanation of Statement 1.
• Statement 1 is CORRECT: Tissues are only found in Multicellular organisms. Since, multicellular organisms have complex biological tasks which are performed by specialised groups of cells. In unicellular organisms, all the functions like ingestion, digestion, locomotion etc is performed by a single cell.
• Statement 2 is CORRECT and is the CORRECT explanation of statement 1: For efficient functioning of organs and organ system in a multicellular organism. Some of the common tissues are blood, muscles etc. -
Question 17 of 20
17. Question
With reference to the plant tissues, consider the following pairs:
Tissues – Functions
1. Parenchyma – Food storage
2. Collenchyma – Flexibility in plants
3. Sclerenchyma – Mechanical strength in plants
How many of the above pairs are correctly matched?Correct
Answer: C
Explanation:
Simple permanent tissues in plants are broadly classified into 3 types – Parenchyma, Collenchyma and Sclerenchyma.
• Pair 1 is CORRECT: Parenchyma is involved in the storage of food. It is made up of cellulose and comprises a thin cell wall. In addition to photosynthesis and storing cooked food, they are also helpful in gas trading.
• Pair 2 is CORRECT: Collenchyma provide flexibility in plants. It allows bending of various parts of a plant like tendrils and stems of climbers without breaking.
• Pair 3 is CORRECT: It makes the plant hard and stiff. For example – husk of a coconut is made up of sclerenchyma.Incorrect
Answer: C
Explanation:
Simple permanent tissues in plants are broadly classified into 3 types – Parenchyma, Collenchyma and Sclerenchyma.
• Pair 1 is CORRECT: Parenchyma is involved in the storage of food. It is made up of cellulose and comprises a thin cell wall. In addition to photosynthesis and storing cooked food, they are also helpful in gas trading.
• Pair 2 is CORRECT: Collenchyma provide flexibility in plants. It allows bending of various parts of a plant like tendrils and stems of climbers without breaking.
• Pair 3 is CORRECT: It makes the plant hard and stiff. For example – husk of a coconut is made up of sclerenchyma. -
Question 18 of 20
18. Question
Consider the following statements:
1. While tendons connect muscles to bones, ligament connects bone to bone.
2. Ligaments are more elastic than tendons.
Which of the statements given above is/are correct?Correct
Answer: C
Explanation:
Ligaments and tendons are fibrous tissues which support the skeletal system of animal body. Each muscle contains only one tendon whereas each joint contains many ligaments. A tendon injury will typically cause increased pain with contraction of the tendon’s associated muscle, while a ligament injury will not cause pain since ligaments attach bone to bone. Both types of injuries, however, can result in increased pain with joint movement.
1. Statement 1 is CORRECT: Tendons connect muscles to bones whereas ligaments connect bone to bone.
2. Statement 2 is CORRECT: Tendons are fibrous tissues with great strength but limited flexibility whereas, ligament joints are very elastic.Incorrect
Answer: C
Explanation:
Ligaments and tendons are fibrous tissues which support the skeletal system of animal body. Each muscle contains only one tendon whereas each joint contains many ligaments. A tendon injury will typically cause increased pain with contraction of the tendon’s associated muscle, while a ligament injury will not cause pain since ligaments attach bone to bone. Both types of injuries, however, can result in increased pain with joint movement.
1. Statement 1 is CORRECT: Tendons connect muscles to bones whereas ligaments connect bone to bone.
2. Statement 2 is CORRECT: Tendons are fibrous tissues with great strength but limited flexibility whereas, ligament joints are very elastic. -
Question 19 of 20
19. Question
With reference to diversity in the living organisms, consider the following statements:
1. Some fungi can perform photosynthesis.
2. Some plants can be heterotrophs.
3. Some animals can be non-mobile.
How many of the above statements are correct?Correct
Answer: B
Explanation:
All living beings are broadly classified into 5 Kingdoms based on cell structure, mode and source of nutrition and body organisation. It is based on the classification of Robert Whittaker. These are:
1. Monera
2. Protista
3. Fungi
4. Plantae
5. Animalia
• Statement 1 is INCORRECT: Fungi are multicellular organisms and are not capable of photosynthesis. This difference in the mode of nutrition is the parameter of differentiation between plants and fungi. They are heterotrophic because they use complex organic compounds as sources of energy and carbon.
• Statement 2 is CORRECT: Although most of the plants are autotrophs as they photosynthesize their own food. But some plants like – Pitcher plant and Venus Fly Trap are heterotrophs. They are also known as insectivorous plants. They depend on others for food.
• Statement 3 is CORRECT: Porifera are non-motile animals attached to some solid support. They are commonly known as Sponges and are commonly found in marine habitat.Incorrect
Answer: B
Explanation:
All living beings are broadly classified into 5 Kingdoms based on cell structure, mode and source of nutrition and body organisation. It is based on the classification of Robert Whittaker. These are:
1. Monera
2. Protista
3. Fungi
4. Plantae
5. Animalia
• Statement 1 is INCORRECT: Fungi are multicellular organisms and are not capable of photosynthesis. This difference in the mode of nutrition is the parameter of differentiation between plants and fungi. They are heterotrophic because they use complex organic compounds as sources of energy and carbon.
• Statement 2 is CORRECT: Although most of the plants are autotrophs as they photosynthesize their own food. But some plants like – Pitcher plant and Venus Fly Trap are heterotrophs. They are also known as insectivorous plants. They depend on others for food.
• Statement 3 is CORRECT: Porifera are non-motile animals attached to some solid support. They are commonly known as Sponges and are commonly found in marine habitat. -
Question 20 of 20
20. Question
Consider the following features:
1. Warm blooded animals
2. Four chambered hearts
3. Lay eggs
How many of the features mentioned above define the characteristics of birds?Correct
Answer: C
Explanation:
Vertebrate animals are grouped into six classes based on factors like- mode of sexual reproduction, scales on body, warm blooded or cold-blooded feature, respiration mode etc. These are:
1. Cyclostomata
2. Pisces (or fishes)
3. Amphibia
4. Reptiles
5. Aves (or birds)
6. Mammals
• 1st Feature is CORRECT: Like mammals, birds are warm blooded. This means that they can maintain a constant body temperature by generating internal heat.
• 2nd Feature is CORRECT: All birds have four chambered heart like human beings. Four chambers are – 2 Atria and 2 Ventricles.
• 3rd Feature is CORRECT: Birds are oviparous. It means that they lay eggs. Viviparous animals, like mammals, give birth to young ones.Incorrect
Answer: C
Explanation:
Vertebrate animals are grouped into six classes based on factors like- mode of sexual reproduction, scales on body, warm blooded or cold-blooded feature, respiration mode etc. These are:
1. Cyclostomata
2. Pisces (or fishes)
3. Amphibia
4. Reptiles
5. Aves (or birds)
6. Mammals
• 1st Feature is CORRECT: Like mammals, birds are warm blooded. This means that they can maintain a constant body temperature by generating internal heat.
• 2nd Feature is CORRECT: All birds have four chambered heart like human beings. Four chambers are – 2 Atria and 2 Ventricles.
• 3rd Feature is CORRECT: Birds are oviparous. It means that they lay eggs. Viviparous animals, like mammals, give birth to young ones.
