Question 1

Consider the following types of vehicles:
1. Full battery electric vehicles
2. Hydrogen fuel cell vehicles
3. Fuel cell electric hybrid vehicles

How many of the above are considered as alternative powertrain vehicles?

Accepted Answer

Only two. * A powertrain is the system in a vehicle that generates power and delivers it to the wheels (engine, transmission, drivetrain, axles, differentials, etc.). * All three vehicle types are considered alternative powertrain vehicles because they use non-conventional propulsion systems compared to traditional internal combustion engines (ICE). * I. Full battery electric vehicles (BEVs) are powered entirely by electricity stored in batteries and use non-ICE systems. * II. Hydrogen fuel cell vehicles (FCEVs) use hydrogen fuel cells to generate electricity to power electric motors. * III. Fuel cell-electric hybrid vehicles combine a fuel cell with a battery or other electric storage system.

Question 2

In the context of electric vehicle batteries, consider the following elements:
I. Cobalt
II. Graphite
III. Lithium
IV. Nickel

How many of the above usually make up battery cathodes?

Accepted Answer

Only two. * Element I is correct: Cobalt is commonly used in cathodes of batteries like Lithium Cobalt Oxide (LCO) and NMC (Nickel Manganese Cobalt) to improve energy density and battery life. * Element II is incorrect: Graphite is the most common material used in the anodes, not the cathodes, of lithium-ion batteries. * Element III is correct: Lithium is present in both cathodes and electrolytes, forming compounds like $LiCoO_{2}$ or $LiFePO_{4}$ in the cathode. * Element IV is correct: Nickel is used in cathodes (like NMC and NCA) to enhance energy density and storage capacity. * Therefore, three elements usually make up battery cathodes.

Question 3

Consider the following substances:
I. Ethanol
II. Nitroglycerine
III. Urea

Coal gasification technology can be used in the production of how many of them?

Accepted Answer

Only one. * Coal gasification converts coal into syngas (CO and $H_2$), which acts as a feedstock for chemical and fuel production. * Option 1 is correct: Syngas from coal gasification can be fermented using specialized anaerobic microorganisms to synthesize ethanol. * Option 2 is incorrect: Nitroglycerine is a vasodilatory drug used primarily to relieve anginal chest pain and is not produced using coal gasification technology. * Option 3 is correct: Coal gasification can be used to produce ammonia, which is then utilized to manufacture urea fertilizers (e.g., the integrated coal gasification-based urea plant at Talcher, Odisha). * Therefore, coal gasification can be used to produce two of the substances.

Question 4

With reference to 'Direct Air Capture', an emerging technology, which of the following statements is/are correct?
1. It can be used as a way of carbon sequestration.
2. It can be a valuable approach for plastic production and in food processing.
3. In aviation, it can be a source of carbon for combining with hydrogen to create synthetic low-carbon fuel.

Select the correct answer using the code given below.

Accepted Answer

III only. * Statement I is correct: Direct Air Capture (DAC) extracts CO2 directly out of the ambient atmosphere, which can then be permanently sequestered in deep geological formations. * Statement II is correct: The captured atmospheric carbon can be used as an industrial chemical feedstock to manufacture carbon-based materials like plastics, and used in food processing fields (e.g., beverage carbonation or preservatives). * Statement III is correct: In aviation, DAC-captured CO2 can be combined with green hydrogen via Power-to-Liquid (PtL) processing to synthesize low-carbon e-fuels, which help decarbonize long-haul flights.

Question 5

Consider the following statements:
Statement I: Some rare earth elements are used in the manufacture of flat television screens and computer monitors.
Statement II: Some rare earth elements have phosphorescent properties.

Which one of the following is correct in respect of the above statements?

Accepted Answer

Both Statement I and Statement II are correct and Statement II explains Statement I. * Statement I is correct: Rare earth elements like europium, terbium, and yttrium are standard components utilized in manufacturing flat-screen TVs and computer monitors. * Statement II is correct: These elements possess distinct phosphorescent (luminescent) properties, meaning they emit visible light when excited by energy. This property directly explains why they are used to generate vivid colors in display screens, making Statement II the correct explanation for Statement I.

Question 6

Artificial way of causing rainfall to reduce air pollution makes use of:

Accepted Answer

silver iodide and potassium iodide. * Artificial rain (cloud seeding) is commonly conducted using silver iodide (Agl) and occasionally potassium iodide (KI). * These chemical compounds function as highly effective cloud condensation or ice nuclei, allowing water droplets to coalesce and precipitate as rain to clean the air.

Question 7

Consider the following:
1. Battery storage
2. Biomass generators
3. Fuel cells
4. Rooftop solar photovoltaic units

How many of the above are considered "Distributed Energy Resources"?

Accepted Answer

Only three. * Items 1, 2, 3, and 4 are correct: Distributed Energy Resources (DERs) include any small-scale, decentralized technologies or devices that can produce, store, or manage electricity situated close to the consumer's end of the meter. * This classification covers rooftop solar photovoltaic arrays, localized small wind turbines, biomass generators, fuel cells, and micro-scale battery storage units. Thus, all four are DERs.

Question 8

In which of the following are hydrogels used?
1. Controlled drug delivery in patients
2. Mobile air-conditioning systems
3. Preparation of industrial lubricants

Select the correct answer using the code given below:

Accepted Answer

2 and 3 only. * Application 1 is correct: Because hydrogels consist of highly cross-linked, biocompatible hydrophilic polymer networks that swell in fluids, they serve as excellent vehicles to enable time-controlled localized drug delivery in patients. * Application 2 is correct: Their high water-retention and evaporative characteristics are increasingly leveraged to build passive cooling loops and custom components for air-conditioning and electronics systems. * Application 3 is correct: Advanced research indicates that hydrogels can operate as highly efficient industrial bio-lubricants due to their excellent anti-friction and wear-resistant properties.

Question 9

Which one of the following is the exhaust pipe emission from Fuel Cell Electric Vehicles, powered by hydrogen?

Accepted Answer

Oxygen. * (d) Water vapour is correct: Fuel Cell Electric Vehicles (FCEVs) use onboard fuel cells to combine compressed hydrogen gas with atmospheric oxygen, generating electricity to drive an electric motor. This clean electrochemical process generates no toxic tailpipe pollution, releasing only pure water vapor and warm air as byproducts.

Question 10

Recently, the term "pumped-storage hydropower" is actually and appropriately discussed in the context of which one of the following?

Accepted Answer

Lift irrigation. * (c) Long duration energy storage is correct: Pumped-Storage Hydropower (PSH) is a configuration of two water reservoirs placed at different elevations. During periods of low power demand, cheap excess grid electricity is used to pump water up to the higher reservoir. When demand peaks, the water is released downward to spin turbines and generate power, acting as a massive, highly efficient long-duration utility energy storage system.

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