ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>QUESTIONS>Q 4

HARD

11th ICSE

IMPORTANT

Earn 100

State Kirchhoff's law of radiation and prove it.

Important Questions on Thermal Radiation

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>QUESTIONS>Q 5

State Stefan's law of thermal radiation. Established Newton's law of cooling from this law.

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>QUESTIONS>Q 6

Define solar constant. How does one estimate the surface temperature of the sun?

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>QUESTIONS>Q 7

Define a perfectly black body. Draw the spectral distribution curve of the black body and write the effect of rising of temperature on it.

MEDIUM

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>NUMERICALS>Q 1

Compute the rate of emission of energy per unit area from the black body maintained at

1200 K

.

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>NUMERICALS>Q 2

A black coated metallic ball of radius $1 cm$ is heated to $327 ° C$ . If the temperature of the surrounding is $27 ° C$ , at what rate the heat be emitted by the ball.

HARD

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>NUMERICALS>Q 3

Nearly

8.37 J \min^{- 1} {cm}^{- 1}

energy is received on the earth from the sun. If the solar energy radiated falling on an area of

10 m^{2}

is given to

100 gm

of water at

0 ° C

filled in a cup, in how much time the water will boil? sp.heat of water

1.0 cal {gm}^{- 1} ° C^{- 1}

.

MEDIUM

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>NUMERICALS>Q 5

A black body radiates

5000 J s^{- 1}

energy at

227 ° C

. What will be the rate of radiation at

727 ° C

?

EASY

11th ICSE

IMPORTANT

ISC Physics Class XI Part 1>Chapter 25 - Thermal Radiation>NUMERICALS>Q 6

If the temperature of black body is increased from

273 ° C to 819 ° C

, then how many times the rate of radiation will increase?