9D) Physics (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

2] 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

3] 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

4] 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

5] 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

6] 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

7] 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

8] 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

9] 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

10] 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

11] 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

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