9D) Physics (Prelims PYQs)

Last Updated on October 24, 2024 by Admin

2024 Prelims PYQs

1] With reference to radioisotope thermoelectric generators (RTGs), consider the following statements: [2024]

1. RTGs are miniature fission reactors.
2. RTGs are used for powering the onboard systems of spacecrafts.
3. RTGs can use Plutonium-238, which is a by-product of weapons development.

Which of the statements given above are correct?
a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

Show Answer

Ans: b) 2 and 3 only

2023 Prelims PYQs

1] Consider the following statements: [2023]

Statement-I :
India, despite having Uranium deposits, depends on coal for most of its electricity production.

Statement- II:
Uranium, enriched to the extent of at least 60%, is required for the production of electricity.

Which of the following is correct in respect of the above statements?
a) Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I.
b) Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-I.
c) Statement-I is correct but Statement-II is incorrect.
d) Statement-I is incorrect but Statement-II is correct.

Show Answer

Ans: c) Statement-I is correct but Statement-II is incorrect.

2022 Prelims PYQs

1] Which one of the following-is the context in which the term “qubit” is mentioned? [2022]

a) Cloud Services
b) Quantum Computing
c) Visible Light Communication Technologies
d) Wireless Communication Technologies

Show Answer

Ans: b) Quantum Computing

2021 Prelims PYQs

1] With reference to street-lighting, how do sodium lamps differ from LED lamps? [2021]

1) Sodium lamps produce light in 360 degrees but it is not so in the case of LED lamps.
2) As street-lights, sodium lamps have longer life span than LED lamps.
3) The spectrum of visible light from sodium lamps is almost monochromatic while LED lamps offer significant colour advantages in street-lighting.
4) Select the correct answer using the code given below.

a) 3 only
b) 2 only
c) 1 and 3 only
d) 1, 2 and 3

Show Answer

Ans: c) 1 and 3 only

2] In a pressure cooker, the temperature at which the food is cooked depends mainly upon which of the following? [2021]

1) Area of the hole in the lid
2) Temperature of the flame
3) Weight of the lid

Select the correct answer using the code given below.
a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

Show Answer

Ans: c) 1 and 3 only

2017 Prelims PYQs

1] Organic Light Emitting Diodes (OLEDs) are used to create digital display in many devices. What are the advantages of OLED displays over Liquid Crystal displays? [2017]

1. OLED displays can be fabricated on flexible plastic substrates.
2. Roll-up displays embedded in clothing can be made using OLEDs.
3. Transparent displays are possible using OLEDs.

Select the correct answer using the code given below
a) 1 and 3 only
b) 2 only
c) 1, 2 and 3
d) None of the above statements is correct

Show Answer

Ans: c) 1, 2 and 3

2016 Prelims PYQs

1] India is an important member of the ‘International Thermonuclear Experimental Reactor’. If this experiment succeeds, what is the immediate advantage for India? [2016]

a) It can use thorium in place of uranium for power generation
b) It can attain a global role in satellite navigation
c) It can drastically improve the efficiency of its fission reactors in power generation
d) It can build fusion reactors for power generation

Show Answer

Ans: d) It can build fusion reactors for power generation

2014 Prelims PYQs

1] With reference to technology for solar power production, consider the following statements: [2014]

1. ‘Photovoltaics’ is a technology that generates electricity by direct conversion of light into electricity, while ‘Solar Thermal’ is a technology that utilizes the Sun’s rays to generate heat which is further used in electricity generation process.
2. Photovoltaics-generates Alternating Current (AC), while Solar Thermal generates Direct Current (DC).
3. India has manufacturing base for Solar Thermal technology, but not for photovoltaics.

Which of the statements given above is/are correct?
a) 1 only
b) 2 and 3 only
c) 1, 2 and 3
d) None

Show Answer

Ans: a) 1 only

2013 Prelims PYQs

1] Ball bearings are used in bicycles, cars, etc., because__: [2013]

a) The actual area of contact between the wheel and axle is increased
b) The effective area of contact between the wheel and axle is increased
c) The effective area of contact between the wheel and axle is reduced
d) None of the statements is correct

Show Answer

Ans: c) The effective area of contact between the wheel and axle is reduced

2] Consider the following phenomena ___: [2013]

1. Size of the sun at dusk
2. Colour of the sun at dawn
3. Moon being visible at dawn
4. Twinkle of stars in the sky
5. Polestar being visible in the sky

Which of the above are optical illusions?
a) 1,2 and 3
b) 3, 4 and 5
c) 1, 2 and 4
d) 2, 3 and 5

Show Answer

Ans: c) 1, 2 and 4

3] Rainbow is produced when sunlight falls on drops of rain. Which of the following physical phenomena are responsible for this? [2013]

1. Dispersion
2. Refraction
3. Internal reflection

Select the correct answer using the codes given below?
a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

Show Answer

Ans: d) 1, 2 and 3

4] The known forces of nature can be divided into four classes, viz., gravity, electromagnetism, weak nuclear force and strong nuclear force. With reference to them, which one of the following statements is not correct? [2013]

a) Gravity is the strongest of the four
b) Electromagnetism acts only on particles with an electric charge
c) Weak nuclear force causes radioactivity
d) Strong nuclear force holds protons and neutrons inside the nucleus of an atom

Show Answer

Ans: a) Gravity is the strongest of the four

5] The efforts to detect the existence of Higgs boson particle have become frequent news in the recent past. What is/ are the importance of discovering this particle? [2013]

1. It will enable us to under-stand as to why elementary particles have mass.
2. It will enable us in the near future to develop the technology of transferring matter from one point to another without traversing the physical space between them.
3. It will enable us to create better fuels for nuclear fission.

Select the correct answer using the codes given below.
a) 1 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3

Show Answer

Ans: a) 1 only

2012 Prelims PYQs

1] A team of scientists at Brookhaven National Laboratory including those from India created the heaviest anti-matter (anti-helium nucleus).: [2012]

What is/are the implication/ implications of the creation of anti-matter?
1. It will make mineral prospecting and oil exploration easier and cheaper.
2. It will help probe the possibility of the existence of stars and galaxies made of anti-matter.
3. It will help understand the evolution of the universe.

Select the correct answer using the codes given below:
a) 1 Only              b) 2 & 3 only
c) 3 Only              d) 1,2 & 3

Show Answer

Ans: b) 2 & 3 only

2] Consider the following statements If there were no phenomenon of capillarity: [2012]

1. It would be difficult to use a kerosene lamp
2. One would not be able to use a straw to consume a soft drink
3. The blotting paper would fail to function
4. The big trees that we see around would not have grown on the Earth

Which of the statements given above are correct?
a) 1, 2 and 3 only              b) 1, 3 and 4 only
c) 2 and 4 only                  d) 1, 2, 3 & 4

Show Answer

Ans: b) 1, 3 and 4 only

3] To meet its rapidly growing energy demand, some opine that India should pursue research and development on Thorium as the future fuel of nuclear energy. [2012]

In this context, what advantage does Thorium hold over uranium?
1. Thorium is far more abundant in nature than uranium.
2. On the basis of per unit mass of mined mineral, thorium can generate more energy compared to natural uranium.
3. Thorium produces less harmful waste in comparison to uranium.

Which of the statements given above is/are Correct?
a) 1 Only                             b) 2 & 3 Only
c) 1 & 3 Only                      d) 1,2 & 3

Show Answer

Ans:   d) 1,2 & 3

2011 Prelims PYQs

1] The function of heavy water in a nuclear reactor is to? [2011]

a) Slow down the speed of neutrons.
b) Increase the speed of neutrons.
c) Cool down the reactor.
d) Stop the nuclear reaction.

Show Answer

Ans:   a) Slow down the speed of neutrons.

2] What is the difference between a CFL and an LED lamp? [2011]

1) To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semi-conductor material.
2) The average life span of a CFL is much longer than that of an LED lamp.
3) A CFL is less energy-efficient as compared to an LED lamp.

Which of the statements given above is/are correct?
a) 1 only                             b) 2 and 3 only
c) 1 and 3 only                  d) 1,2,and 3

Show Answer

Ans:   c) 1 and 3 only  

3] A new optical disc format known as the blu-ray disc (BD) is becoming popular. In what way is it different from the traditional DVD? [2011]

1. DVD supports standard definition video while BD supports high definition video.
2. Compared to a DVD, the BD format has several times more storage capacity.
3. Thickness of BD is 2.4 mm while that of DVD is 1.2 mm.

Which of the statements given above is/are correct?
a) 1 only                             b) 1 and  2 only
c) 2 and 3 only                  d) 1,2 and 3

Show Answer

Ans:   b) 1 and  2 only

4] The surface of a lake is frozen in severe winter, but the water at its bottom is still liquid. What is the reason? [2011]

a) Ice is a bad conductor of heat.
b) Since the surface of the lake is at the same temperature as the air, no heat is lost.
c) The density of water is maximum at 4°c.
d) None of the statements (a), (b) and (c) given is correct.

Show Answer

Ans:   c) The density of water is maximum at 4°c.

2010-1995 Prelims PYQs