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Science & Tech Examination

  Nov 27, 2021

Science & Tech Examination

Main Examination Pattern


  • Answer all FIVE of the following questions.
  • Time: 1 Hour
  • Each answer should be within 250 words.
  • Please email your answer sheet on Please mention your name, batch and Test Paper name in Subject line.

Que. 1. “Improving the Haber-Bosch process may go a long way in providing food security to the world.”  What is the Haber-Bosch process? How can quantum computing help in this? 
Answer: It is said that quantum computing could end world hunger. The answer lies in the way fertilizer is made – principally from ammonia. The Haber-Boschprocess, by which ammonia is artificially made, is long due for an upgrade since its creation in the early 1900s. It is expensive, like most high pressure high heat processes, and the catalysts used have changed little in industry since its beginnings.
The ammonia industry is important to the way we grow food.
Quantum computing comes into play by providing a new way to improve the catalysts used in the production of ammonia. A catalyst, by definition, lowers the activation energy of a reaction, meaning it takes less energy input (generally in the form of heat) to cause the forward reaction. Finding a better catalyst could dramatically reduce the cost of Haber-Bosch process by reducing the overhead necessary for heat and pressure in the reaction. In the search for a better catalyst, quantum computing modeling ability will positively contribute. It can make testing and selection of catalysts relatively simple in terms of time and cost. It makes difficult modeling calculations relatively inexpensive, in terms of time to compute, and will increase the number of catalysts testable in a short amount of time.
Quantum computing takes advantage of the strange ability of subatomic particles to exist in more than one state at any time. Due to the way the tiniest of particles behave, operations can be done much more quickly and use less energy than classical computers. In classical computing, a bit is a single piece of information that can exist in either of the two states – 1 or 0. Quantum computing uses quantum bits, or 'qubits' instead. These are quantum systems with two states.
Unlike a usual bit, they can store much more information.
Que. 2. Energy storage is one of the most crucial and critical components of India’s energy infrastructure strategy and also for supporting India’s sustained thrust to renewables for which the present target is 175 GW by 2022. Elucidate. Why are the Lithium ion batteries being preferred? Account for the price fall for the batteries.
Answer: With no facility to store electricity as of now, the electricity produced in the power plants and fed into the grid should ideally be the same as the electricity consumed. If the electricity demand is more than the supply, the frequency at which the grid equilibrium is maintained (50 Hertz) will come down and vice versa. An imbalance in frequency when it goes beyond permissible limits leads to grid collapse and blackout (power outage).
Since solar radiation and wind speed keep varying, the frequency cannot be maintained at 50 Hz. Electricity demand also keeps varying. Hence grid operators cannot match supply and demand, if only power from renewable sources is fed into the grid. Since these technical limitations hamper more absorption of renewable energy, a mix of thermal and hydro power are used for maintaining the balance, since power output from these plants can be controlled.
India has a target of 175 GW of renewables by 2022. As the country transitions more towards renewable energy sources, it is becoming imperative to ensure grid stability. One of the solutions for a balanced grid is energy storage batteries. When the energy generation is more than the demand, it can be stored in the batteries and used when generation comes down and/or demand increases.
Batteries have been in use for long, but not on a scale that could support the grid. Lithium ion, lead acid, redox flow, molten salt (sodium sulphur) are the battery storage technologies that are available today. However, the 2019 Nobel winning Lithium ion (Li-ion) technology dominates the market. Li-ion would be ideal for hourly or daily applications like peak shaving (managing demand to eliminate demand spikes) and grid stability as they have high efficiency and power handling capacity, besides decreasing prices. Further, maintenance required in lithium batteries is very less and they have small footprint due to their high energy density.
India’s first grid-scale battery is at a substation located at Rohini, New Delhi. It has been extensively used for peak load management, deviation settlement mechanism management, etc. and provides enhanced power supply, by addressing various technical issues. 
Battery price which was more than $1,100 per kilowatt-hour (kWh) in 2010, came down to $156/kWh in 2019. The price is expected to reach $100/kWh by 2025; and with the new battery manufacturing facility being proposed in India, prices will come down.
Further improvements in battery technology and more efficient integration into complete energy storage systems are expected to further reduce costs. A large increase in global battery manufacturing associated with deployment of electric vehicles is also expected to reduce battery costs for grid-scale battery storage.
The Energy & Resources Institute has projected that India’s electricity demand would be 2040–2857 TWh by 2030. This would mean increasing the country’s power production. Unless renewable penetration is increased in the grid, emissions would increase, proportion to production.
Storage would improve the operating capabilities of the grid, lower power purchase cost, cater to peak demand and address the variability and intermittency of renewables.
Considering these aspects, batteries can ensure energy security and grid stability while increasing the percentage of renewables. With a maximum life of 30 years, batteries would help decarbonise the power sector and bring down emissions and hence public health issues caused by air pollution.
Key areas for Energy Storage applications: 

  • Integrating renewable energy with transmission grids and distribution grids
  • Setting up rural micro grids with diversified loads or stand-alone systems
  • Developing storage component for electric mobility plans.
Que. 3. What is space junk and how is it produced? Does it pose danger? What is being done about it?
Answer: Since the dawn of the space age in the 1950s, we have launched thousands of rockets and sent even more satellites into orbit. Many are still there, and we face an ever-increasing risk of collision as we launch more.
Space junk, or space debris, is any piece of machinery or debris left by humans in space.
It can refer to big objects such as dead satellites that have failed or been left in orbit at the end of their mission. It can also refer to smaller things, like bits of debris or paint flecks that have fallen off a rocket.
Some human-made junk has been left on the Moon, too.
While there are about 2,000 active satellites orbiting Earth at the moment, there are also 3,000 dead ones littering space. What's more, there are around 34,000 pieces of space junk bigger than 10 centimetres in size and millions of smaller pieces that could prove disastrous if they hit any object.
All space junk is the result of us launching objects from Earth, and it remains in orbit until it re-enters the atmosphere.
Some objects in lower orbits of a few hundred kilometres can return quickly. They often re-enter the atmosphere after a few years and, for the most part, they'll burn up - so they don't reach the ground. But debris or satellites left at higher altitudes of 36,000 kilometres - where communications and weather satellites are often placed in geostationary orbits - can continue to circle Earth for hundreds or even thousands of years.
Some space junk results from collisions or anti-satellite tests in orbit. When two satellites collide, they can smash apart into thousands of new pieces, creating new debris. Countries including the USA, China and India have used missiles to practice blowing up their own satellites. This creates thousands of new pieces of dangerous debris.
Fortunately, collisions are rare: the last satellite to collide and be destroyed by space junk was in 2009. And when it comes to exploring beyond Earth's orbit, none of the limited amount of space junk out there poses a problem.
Hundreds of collision avoidance manoeuvres are performed every year, including by the International Space Station (ISS), where astronauts live.
Que. 4. Messenger RNA (mRNA) vaccines are increasingly being preferred as remedies for various infectious and other diseases. Why? Are there any disadvantages?
Answer: Conventional vaccines contain inactivated disease-causing organisms or proteins made by the pathogen (antigens), which work by mimicking the infectious agent. They stimulate the body’s immune response, so as to prepare the person to respond more rapidly and effectively if exposed to the infectious agent in the future.
RNA vaccines use a different approach that takes advantage of the process that cells use to make proteins: cells use DNA as the template to make messenger RNA (mRNA) molecules, which are then translated to build proteins. 
An RNA vaccine consists of an mRNA strand that codes for a disease-specific antigen. Once the mRNA strand in the vaccine is inside the body’s cells, the cells use the genetic information to produce the antigen. This antigen is then displayed on the cell surface, where it is recognised by the immune system.
A major advantage of RNA vaccines is that RNA can be produced in the laboratory from a DNA template using readily available materials, less expensively and faster than conventional vaccine production.
Benefits of mRNA vaccines over conventional approaches are many. They are 
  • Safety: RNA vaccines are not made with pathogen particles or inactivated pathogen, so are non-infectious. RNA does not integrate itself into the host genome and the RNA strand in the vaccine is degraded once the protein is made.
  • Efficacy: early clinical trial results indicate that these vaccines generate a reliable immune response and are well-tolerated by healthy individuals, with few side effects.
  • Production: vaccines can be produced more rapidly in the laboratory in a process that can be standardised, which improves responsiveness to emerging outbreaks.
The most active areas of research into RNA vaccines are infectious diseases and cancer where there is research ongoing as well as early-stage clinical trials. Work into the use of RNA vaccines to treat allergy is still at the early research stage.
Researchers using conventional approaches have struggled to develop effective vaccines against a number of pathogens, particularly viruses, that cause both acute (Influenza, Ebola, Zika) and chronic (HIV-1, herpes simplex virus) infection. RNA vaccines are being explored as a way to more rapidly and cheaply produce vaccines for these diseases, particularly in response to emerging outbreaks. Clinical trials have been carried out or are ongoing on mRNA vaccines for influenza, HIV-1, rabies and Zika virus. 

However, there are technical challenges to overcome to ensure these vaccines work appropriately:
  • Safety: The mRNA strand in the vaccine may elicit an unintended immune reaction. Better understanding of vaccine adverse effects is needed – these can include inflammation or autoimmune reactions.
  • Production: vaccine production is currently small scale and it is not clear if current methods are capable of epidemic-level vaccine production.
  • Delivery: delivering the vaccine effectively to cells is challenging since free RNA in the body is quickly broken down. 
  • Storage: many RNA vaccines, like conventional vaccines, need to be frozen or refrigerated. It is not suitable for use in countries with limited refrigeration facilities as in the developing world.
  • Research and clinical trials: further research is needed to address technical hurdles such as vaccine stability and delivery. 

It is that the Pfizer vaccine won’t work in India. The storage at minus 80 degrees celsius is not available in India. When the vaccine is brought to zero degrees temperature, its life span is only a maximum of 2 days. Thus, logistically, it is ruled out for India. 
Que. 5. How did 3D printing become useful during the pandemic and the lockdown? What are its inherent advantages?
Answer: What is 3D printing?
3D printing uses a printer to create three-dimensional objects.3D printing, or additive manufacturing, is the construction of a three-dimensional object from a Computer-aided design (CAD). 3D printing involves processes in which material is deposited, joined or solidified under computer control to create a three-dimensional object. The material being added together layer by layer.
What is the relevance of 3D technology to Covid-19?
3D printing enables on-demand solutions for a wide spectrum of needs ranging from personal protection equipment to medical devices and isolation wards. This versatile technology is suited to address supply–demand imbalances caused by socio-economic trends and disruptions in supply chains.
Why does it acquire additional importance during the Covid times?
The global uncertainty created by the COVID-19 pandemic has plunged the world into a crisis that is still unfolding. Logistical challenges owing to disruptions in manufacturing and transportation, together with backlashes against globalization and free trade, have constrained supply chains, resulting in critical shortages of essential goods. 
Healthcare systems are on a war footing to increase their capacity of beds, supplies and trained workers. Crisis-response efforts are in motion to alleviate shortages of much-needed medical supplies.
With what specific inputs can 3D printing help?
There is a need for factories to manufacture, on demand, materials and devices for a range of essential services, in particular for healthcare. In this context, a resilient advanced manufacturing network enabled by a distribution of 3D-printing factories has great potential. These ‘art-to-part’ factories can be co-located at hospitals and transportation hubs to quickly serve the needs of the medical profession. 3D printing has redeployed its capabilities for efficient COVID-19 responses, demonstrating its competitive advantage in this emergency situation.
What are the advantages of 3D printing in tackling the pandemic?
The digital versatility and quick prototyping of 3D printing empowers a swift mobilization of the technology and hence a rapid response to emergencies. Even during severe disruptions in supply chains, critical parts can be manufactured on-demand by any decentralized 3D-printing facility in the world by leveraging designs shared online. Moreover, the additive nature of 3D printing enables product customization and complex designs. The broad spectrum of 3D-printing applications in the fight against COVID-19 includes personal protective equipment (PPE), medical, and testing devices, personal accessories, visualization aids and emergency dwellings.
3D printing is being used to provide many different solutions to the challenges posed by the COVID-19 pandemic, ranging from personal protective equipment (PPE) to emergency dwellings to isolate patients.
Is the 3D printing environment-friendly?
In view of addressing the environmental concerns on medical waste accumulated from disposable PPE, 3D printing offers promising solutions to conserve precious resources by advocating recyclable materials and reusability of respirators and filters.
How can it help in training the health workers?
3D printing is being used to provide training and visualization aids for healthcare workers to cope with the limited pool of trained personnel. 
Can it print huge buildings for relieving the load on hospitals?
Yes.  3D printing has been used to fabricate temporary emergency dwellings to isolate those under quarantine, relieving the overloaded medical infrastructures. Compared to traditional construction methods, 3D printing of buildings usually requires shorter building times and lower labour costs, and can use more environmentally friendly raw materials. 3D-printed dwellings can also be easily transported and deployed to areas where they are most needed.
How is it developing in India? What are the capabilities and challenges?
3D printing industry in India is still nascent. In India, many big and small firms offer 3D-printing services for a few industry sectors, such as medical and automobiles. It has large-scale value chain dependencies. These include the physical hardware: the printer; the software; the material – metal/non-metal; and 3D-printing service providers. It is heavily reliant on the U.S. and Europe for hardware, software and material sourcing. The ongoing pandemic has exposed these dependencies and severely limited the scalability of 3D-printing in India.
In addition to the above hurdles is the issue of collaboration. For India to emerge as a competitive player in 3D printing, the IT hardware and software companies must collaborate with each other and co-invest in R&D for developing a home-grown 3D-printing ecosystem to achieve value chain independence, rapid prototyping and manufacturing capabilities – all crucial requirements in a post-COVID-19 era.