IASbaba's Think Learn and Perform 2017, UPSC Mains Answer Writing
SYNOPSIS: IASbaba’s TLP – 2017 : UPSC Mains General Studies Questions [6th Sep, 2017]- Day 43
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1. GaN was in news recently. What is GaN? Why has it evoked interest? What are its applications? Discuss.
Introduction:
Gallium nitride (GaN) is a semiconductor commonly used in light-emitting diodes since the 1990s. The compound is a very hard material that has a Wurtzite crystal structure. Its wide band gap of 3.4 eV affords it special properties for applications in optoelectronic,[7][8]high-power and high-frequency devices.
It has evoked interest because of following attributes:
- lower on resistance giving lower conductance losses
- faster devices yielding less switching losses
- less capacitance resulting in less losses when charging and discharging devices
- less power needed to drive the circuit
- smaller devices taking up less space on the printed circuit board. GaN transistors can withstand higher electric fields, which in turn, increases power density and makes the device smaller.
- lower cost
Applications of GaN:
- Its sensitivity to ionizing radiation is low (like other group III nitrides), making it a suitable material for solar cell arrays for satellites.
- Military and space applications could also benefit as devices have shown stability in radiation environments.
- Because GaN transistors can operate at much higher temperatures and work at much higher voltages than gallium arsenide (GaAs) transistors, they make ideal power amplifiers at microwave frequencies.
- GaN semiconductor devices are already in use in LEDs and power amplifiers for 4G radio base stations, and now GaN-based transistors are becoming a key enabling technology in power electronics products like adapters, power supplies, and solar inverters. GaN is used to manufacture light-emitting diodes (LEDs) with colors that can go from red to ultra-violet.
- GaN-based electronics (not pure GaN) has the potential to drastically cut energy consumption, not only in consumer applications but even for power transmission utilities. Their transistors have much less resistance as compared to silicon-based transistors. This allows for much higher energy efficiency, and orders-of-magnitude faster switching frequency. This has huge implications not only for energy usage of power electronics systems, but their physical size and stability.
- GaN nanotubes are proposed for applications in nanoscale electronics, optoelectronics and biochemical-sensing applications.
Conclusion:
Of course, the unique properties of GaN holds potential to transform various sectors including power, defence, aerospace, medical etc. However, certain challenges like its high cost and its dust being irritant to skin, eyes and lungs needs to be overcome before the scientific community move forward.
Best answer: Nana
2. Science infrastructure sharing to enable opening out of scientific resources to other universities and the industry is a much needed policy to enhance academy-industry collaboration. Do you agree? Substantiate. Also examine the benefits of such policy.
SYNOPSIS:
The national science policy formulated in 2013 envisages 2010-2020 as a decade of innovation, in order to fulfill this vision it is not only necessary to invest in R&D but also make sure that this investment is used prudently and judiciously.
SCIENCE INFRASTRUCTURE SHARING POLICY: One of the glaring lapses in our scientific endeavors is the lack of coordination between institutions and the industry academia disconnect, this policy aims to bridge the gap in that direction.
The idea of such a policy is to see that infrastructure granted to academic institutions, Government labs can be shareable, accessible and sustainable to the industry. A web portal is being envisaged to implement the policy. In a website, anybody can book a slot and put in a request to access instruments in different labs. One example of such infrastructure sharing is the EU-funded PAERIP project to share resources between Europe and Africa. PAERIP created the first-ever inventory of research infrastructure in the two continents.
BENEFITS:
- Prevents redundancy of infrastructure of labs
- Prevents duplication of efforts in labs for eg: IICT, NCL, IDL (PSU) can coordinate the efforts together.
- Prioritize allocation of funds to some other purposes rather than spending on equipment which can be costly.
- Industry – academia interlink can help in skill development, employment opportunities, research focused on market demands, helps in scalability.
- Acts as a source of revenue to the labs which are often starved for funds and have to depend on Government grants for the same. Eg: JNCASR under the aegis of Dr.CNR Rao in Bangalore is already implementing a plan in this mode.
- Prevents tricky IPR issues if all the bodies are working together on the same projects.
- Can lead India into an era of industry led innovation which has so far remained minimal.
Since it’s a policy, not a law, the challenge lies in implementation. There is a need to make people aware of the idea contained in the policy and let them see the value for themselves.
BEST ANSWER: AKS
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3. What is hyper loop transportation? Who are the major players in this technology? Does it have a potential in India? Examine.
Introduction
Hyperloop is a mode of passenger and freight transportation that propels a pod like vehicle in reduced pressure tubes at speeds greater than that of airlines.
The science and technology involved
- Near vacuum tubes-to cut down air resistance and boost speed of vehicle.
- Magnetic levitating/Air bearing-To overcome physical friction.
- Linear Electric induction motors-to accelerate/decelerate the vehicle in forward direction to attain desired speed.
- Compressor-To shift high pressure generated in front of train to its rear to get higher speed.
Main Body
The concept of the Hyperloop was popularized by Elon Musk,founder and CEO of spaceX.Major players involved in this technology are Hyperloop one and Hyperloop transportation technologies.
Indian tink tank NITI aayog is viewing Hyperloop has future mode of transportation.Some pilots are already in the works likepod-taxi pilot, with Metrino-PRT. Hyperloop has capacity to revolutionize Indian mode of transport because
- It will reduce the time of travel at the same time enhancing the connectivity.
- It will share the burden of freight and passengers with overburdened railways and airways.
- It is comparatively cheaper than other high speed/bullet trains.
- It can be build underground and above ground on columns and hence is flexible to diverse Indian Topography.
- If coupled with green energy it will become more energy efficient mode of travel.
Challenges
- The cost of the hyperloop is expected to run into billions of dollars which is another issue for financial reasons and will be difficult without subsidies.
- Not a single Hyperloop prototype has been tested worldwide, thus its safety is unproven.
- Large travelling crowd in India where as each capsule can accommodate only a few people.
- Health concerns, High acceleration can produce nausea, straining of muscles etc.
- At the same time it has some unresolved issues associated with it like security in case of terror attacks and other malfunctions in system,etc.
Conclusion
Rapid and increased connectivity is the demand of time and with its caliber and wisdom in fields of science and technology coupled with holistic research and development, India can become a pioneer in developing Hyperloop transport system with its knowledge and engineering skills.
Best Answer: NKY
4. Discuss the contribution of CV Raman in the field of science.
What is Raman Effect:
Raman effect, change in the wavelength of light that occurs when a light beam is deflected by molecules. When a beam of light traverses a dust-free, transparent sample of a chemical compound, a small fraction of the light emerges in directions other than that of the incident (incoming) beam. Most of this scattered light is of unchanged wavelength. A small part, however, has wavelengths different from that of the incident light; its presence is a result of the Raman effect.
Raman scattering is perhaps most easily understandable if the incident light is considered as consisting of particles, or photons (with energy proportional to frequency), that strike the molecules of the sample. Most of the encounters are elastic, and the photons are scattered with unchanged energy and frequency. On some occasions, however, the molecule takes up energy from or gives up energy to the photons, which are thereby scattered with diminished or increased energy, hence with lower or higher frequency. The frequency shifts are thus measures of the amounts of energy involved in the transition between initial and final states of the scattering molecule.
The energies corresponding to the Raman frequency shifts are found to be the energies associated with transitions between different rotational and vibrational states of the scattering molecule. Pure rotational shifts are small and difficult to observe, except for those of simple gaseous molecules. In liquids, rotational motions are hindered, and discrete rotational Raman lines are not found. Most Raman work is concerned with vibrational transitions, which give larger shifts observable for gases, liquids, and solids. Gases have low molecular concentration at ordinary pressures and therefore produce very faint Raman effects; thus liquids and solids are more frequently studied.
For the discovery of Raman Effect, He was awarded Nobel Prize on 28th February 1930 (Celebrated as National Science Day in India)
In 1932, Raman and Suri Bhagavantam discovered the quantum photon spin. This discovery further proved the quantum nature of light.
Raman was the first person to investigate the harmonic nature of the sound of Indian drums such as tabla and mridangam.
Best Answer: Warrior ias.
5. What is Kigali Amendment? Why is it a significant step against climate change? Examine.
Introduction:
With growth and development came destruction of atmosphere, one among them was Ozone hole. To stop it, Montreal protocol was initiated in 1987, which needed certain amendments which lead at Kigali in 2016 Known as Kigali Amendment.
Body:
- In the 28thmeeting of the Parties to the Montreal Protocol, a historic agreement was signed between 197 countries.
- As per the agreement, these countries are expected to reduce the manufacture and use of Hydrofluorocarbons (HFCs)by roughly 80-85% from their respective baselines, till 2045.
It is a significant step in climate change because:
- It is legally binding.
- It also has a provision for a multilateral fundfor developing countries for adaptation and mitigation.
- Periodic review by committee for energy efficiency and safety
- It strengthens the Paris Agreement wyhich sets an ambitious target of restricting the rise in global temperature below 2O Celsius, as compared to pre-industrial level.
- Unlike Paris agreement, it gives clear, concrete and mandatory targets withfixed timelines to the signatory parties to achieve their targets.
- It would prevent the emission of HFCs equivalent to 70 billion tons of CO2.
Conclusion:
Kigali agreement is a very significant step and has got support from most of the countries due to its grouping and time levels. The replacement technology is already available known as Hydro fluro olefin (HFO), so the shift may not be so difficult to achieve in decades.
Best Answer: Azor_Ahai
