# GK Questions: General Science(Physics) – Set 20

Hello Aspirants. Welcome to Online General Knowledge section in Affairs cloud, which is important for all the competitive exams. We have created Some questions related to General Science(Physics) !!

1. If lift is stationary or moving with uniform speed, the apparent weight of a body is ………….. true weight
1.More than the
2.Equal to its
3.Less than the
4.Become zero
5.None of these
Explanation :
If lift is stationary or moving with uniform speed ( either down or upward) , the apparent weight of a body is equal to its true weight.

2. Under the elastic limit, stress is proportional to strain according to ………………
1.Hooke’s law
2.Bernoulli’d Theorem
3.Newton’s law
4.Doppler effect
5.None of these
Explanation :
Hooke’s law stating that the strain in a solid is proportional to the applied stress within the elastic limit of that solid.

3. …………………. is the reverse process of sublimation
1.Conditioning
2.Vaporisation
3.Hoar Frost
4.Condensation
5.None of these
Explanation :
Hoar Frost is the reverse process of sublimation.This is a fairly common occurrence in nature and is called hoar frost or hoar ice

4. The region in which region, partial of the light reaches is called as ……..
1.Umbra
2.Opaque
3.Transparent
4.Penumbra
5.None of these
Explanation :
Partial solar eclipses occur when the viewer is inside the penumbra.

5. SI unit of power of lens is …………………….
1.Centimeter
2.Dioptre
3.Meter
4.All of these
5.None of these
Explanation :
A dioptre or diopter  is a unit of measurement of the optical power of a lens or curved mirror, which is equal to the reciprocal of the focal length

6. The velocity of a medium is maximum for that colour for which refractive index is …………..
1.Maximum
2.Minimum
3.Equal
4.Can’t tell
5.None of these
Explanation :
The velocity of a medium is maximum for that colour for which refractive index is Minimum. Refractive Index is maximum for violet and minimum for red colour

7. ……………… is/are example of naturally negative charged material
1.Flannel
2.Shellac
3.Amber
4.Resin
5.All of these
Explanation :
Flannel, Shellac, Amber, Resin are example of naturally negative charged material

8. SI unit of intensity of illumination is ……………………
1.lumen
2.Angstrom
3.Lux
4.Weber
5.None Of These
Explanation :
Lux,  lux meter unit of illumination in the International System of Units (SI). One lux is the amount of illumination provided when one lumen is evenly distributed over an area of one square metre.

9. Sound travels at the fastest speed in …………….
1.Air
2.Water
3.Oil
4.Steel
5.None of these
Explanation :
Sound travels faster in steel than in air

• The speed of sound in air is 344 m/s
• The speed of sound in steel is 5960 m/s
• In fresh water, sound travels at about 1497 m/s

10. Heat stored in water vapour is ……………
1.Latent heat
2.Specific heat
3.Heat resistance
4.All of these
5.None of these