Day-570 | Daily MCQs | UPSC Prelims | CURRENT DEVELOPMENTS

Answer: A
Explanation
Sodium-ion batteries are a type of rechargeable battery just like the commonly known lithium-ion battery, and their overall working principle, set-up and materials are like lithium-ion batteries. However, there are certain benefits of replacing Lithium with Sodium which have attracted the attention of researchers for increasing its scalability and commercialization.
Statement 1 is correct: Sodium-ion batteries have a lower environmental impact than lithium-ion batteries due to the availability of sodium as a more abundant and widely distributed resource. Additionally, the manufacturing process of sodium-ion batteries may be less energy-intensive than lithium-ion batteries.
Statement 2 is correct and is the correct explanation of statement 1: Sodium is one of the most widely distributed elements. It can be extracted from sea water at a relatively less energy intensive process. Since it is widely distributed so it brings down the environmental impact of transportation of raw materials from few places. Also, decentralized generation systems and storage systems can be created which have a lower environmental impact than transmission through various lines.

Answer: D
Explanation
• A dark pattern or deceptive design pattern is a user interface that has been carefully crafted to trick users into doing unnecessary and unwanted things, such as buying overpriced insurance with their purchase or signing up for recurring bills.
• These are done by prompting users into agreeing to certain conditions or clicking a few links. The user interface is made clumsy and deceptive like making cancellation button very small and hard to find, pop-ups which are hard to ignore, deliberately writing important things in smaller fonts and at unusual places on websites.
• Big Tech firms such as Apple, Amazon, Facebook, Microsoft, and Google use dark or deceptive patterns to mold user experience to their advantage.
• It is to be noted that use of dark pattern is not illegal in India currently. However, misleading ads and unnecessary promotions are challenged under the Consumer Protection Act.
Note: Option C explains Dark Web.

Answer: A
Explanation
There are basically two missile systems in operation- ballistic missile system and cruise missile system. Ballistic missiles use projectile motion to attack targets whereas cruise missiles are guided missiles that remain in the atmosphere and fly the major portion of their flight path at an approximately constant speed.
• Statement 1 is correct: Ballistic missiles have more payload carrying capacity as they are fuel efficient.
• Statement 2 is correct and is the correct explanation of statement 1: Since ballistic missile use projectile motion and is assisted by gravity. They carry fuel for only the initial lift off. They are not required to carry extra fuel to maintain speed as is required in cruise missiles. This reduces the mass of the ballistic missile for similar range as compared to cruise missiles. Thus, they can carry extra payload or can reach larger distance. That is why all intercontinental missiles are ballistic in design.

Answer: C
Explanation
A tokamak is a device which uses a powerful magnetic field to confine plasma in the shape of a torus. The tokamak is one of several types of magnetic confinement devices being developed to produce controlled thermonuclear fusion power. The word “tokamak” is derived from a Russian acronym meaning “toroidal chamber with magnetic coils”.
When heated to fusion temperatures, the electrons in atoms dissociate, resulting in a fluid of nuclei and electrons known as plasma. Unlike electrically neutral atoms, a plasma is electrically conductive, and can, therefore, be manipulated by electrical or magnetic fields.

Answer: D

Explanation

5G is the fifth generation of cellular network technology, succeeding 4G LTE. Unlike 3G and 4G before it, 5G isn’t simply an incremental technological advancement but a true leapfrog technology. One of the biggest differences between 5G and its predecessors is speed. 5G offers theoretical speeds of up to 10 gigabits per second, which is more than 30 times faster than the 300Mbps theoretical maximum speed of 4G LTE-Advanced. This technology also uses higher frequency bands than previous generations and is deployable in low-band, mid-band or high-band millimetre-waves from 24 GHz up to 66 GHz. This aspect allows massively faster data transfer speeds and greater bandwidth capacity.

• Statement 1 is incorrect: 5G can operate on a new, high-frequency spectrum called a millimetre wave (mm wave.) This operates on wavelengths between 30 GHz and 300 GHz, in comparison to the 4G LTE’s wavelengths of under 6 GHz. Higher frequency range increases the bandwidth of operation. A bandwidth is the measure of capacity of the network to onboard multiple devices at the same time. A higher bandwidth means more devices can be connected at the same time.

• Statement 2 is incorrect: 5G is more energy efficient than 4G, starting with cell base designs that allow carriers to reduce their energy consumption. More importantly, mobile devices operating in 5G use less energy as well, providing extended battery performance and life span. It’s estimated that energy consumption per bit with 5G is just 10 percent of what 4G requires. Thus, it is a win-win situation as 5G technology ensures high speed at a lower energy input.

• Statement 3 is incorrect: Both 5G as well as 4G offer full duplex mode of communication. There are 3 modes of transmission of data:

1. Simplex mode: It is a mode of transmission in which the flow of data is unidirectional. It means that the participant can do only one task at a time in a single direction. The receiver can only receive data and not send it (and vice versa).

2. Half Duplex mode: It is a mode of transmission in which the flow of data is bi-directional but only in one direction at a time. It means that the receiver can receive as well as send data but can perform only one of these tasks at a time.

3. Full Duplex mode: It is a mode of transmission in which the flow of data is bi-directional. But here, the devices can send as well as receive data simultaneously at the same time. It means that the receiver can receive as well as send data at the very same time without any interference.