NEET Free Online Mock Test - 2019

Register Here

# NEET Physics  Radiation  Practice Q & A

1. Heat energy received by the earth from the sun is due to

 Convection Radiation Reflection of light Transmission of light

Workspace

2. Two stars A and B radiate maximum energy at 3600Å and 3600Å respectively. Then the ratio of absolute temperatures of A and B is

 256: 81 81: 256 3: 4 4: 3

Workspace

3. In which process the rate of transfer of heat is maximum?

 Conduction Convection Radiation In all these heat is transferred with the same velocity

Workspace

4. Solar radiation emitted by sun resembles that emitted by a black body at a temperature of 6000 K. maximum intensity is emitted at a wavelength of about 4800 Å. if the sun were cooled down from 6000 K to 3000 K, then the peak intensity would occur at a wavelength of

 4800 Å 9600 Å 2400 Å 19200 Å

Workspace

5. emissivity of perfectly black body is

 1 2 5 0

Workspace

6. Absorptive power of perfectly black body is

 Zero Infinity One Constant

Workspace

7. The earth intercepts approximately one billionth of the power radiated by the sun. if the surface temperature of the sun were to drop by a factor of 2, the average radiant energy incident on earth per second would reduce by factor of

 2 4 8 16

Workspace

8. If the temperature of the sun is doubled. The rate of energy received on the earth will be increased by a factor of

 2 4 8 16

Workspace

9. A body in a room cools from 90°C to 80°C in 5 minutes. the time taken to cool from 70°C to 60°C is

 Less than 5 minute 5 minute More than 5 minutes Less or more than 5 minutes depending upon the nature of the body

Workspace

10. The process of heat transfer in which heat is transferred with actual migration of medium particles is known as