JavaScript is disabled on your browser. Enable JavaScript to use this site. Learn More

/

16

8

4

2

Star A has radius r surface temperature T while star B has radius 4r and surface temperature. The ratio of the power of two starts, PA : PB is ____.

16 : 1

1 : 16

1 : 1

1 : 4

Suppose the sun expands so that its radius becomes 100 times its present radius and its surface temperature becomes half of its present value. The total energy emitted by it then will increase by a factor of ____.

104

625

256

16

If the temperature of the sun were to be increased from T to 2T and its radius from R to 2R, then the ratio of the radiant energy received on the earth to what it was previously is?

4

16

32

64

At 127o C radiates energy is 2.7 ( 10-3 J/s. At what temperature radiated energy is 4.32 ( 10 6 J/s?

400 K

4000 K

80000 K

40000 K

If the initial temperatures of metallic sphere and disc, of the same mass, radius and nature are equal, then the ratio of their rate of cooling in same environment is ____.

1 : 4

4 : 1

1 : 2

2 : 1

A black body radiates energy at the rate of 1 ( 105 J / s (m2 at temperature of 227o C. The temperature to which it must be heated so that it radiates energy at rate of 1 ( 109J/sm2 is ____.

5000 K

5000 oC

500 K

500 oC

The temperature of the body is increased from –73 o C to 327 o C; the ratio of energy emitted per second is ____.

1 : 3

1 : 81

1: 27

1 : 9

Two spherical black bodies of radii and and with surface temperature and respectively radiate the same power. Then the ratio of and is ____.

Temperature of a black body increases from, the initial energy possessed is 2 KJ, what is its final energy?

32 KJ

320 KJ

1200 KJ

None of the above

The original temperature of a black body is The temperature at which this black body must be raised so as to double the total radiant energy, is ____.

971 K

1190 K

2001 K

1458 K

Two black metallic spheres of radius 4m, at 2000 K and 1m at 4000 K will have ratio of energy radiation as ____.

1 : 1

4 : 1

1 : 4

2 : 1

The energy spectrum of a black body exhibits a maximum around a wavelength. The temperature of the black body is now changed such that the energy is maximum around a wavelength .The power radiated by the black body will now increase by a factor of ____.

A black body is at a temperature 300 K. It emits energy at a rate, which is proportional to ____.

The spectral energy distribution of star is maximum at twice temperature as that of sun. The total energy radiated by star is ____.

twice as that of the sun

same as that of the sun

sixteen times as that of the sun

one sixteenth of sun

Hot water cools from to in the first 10 minutes and to 42° in the next 10 minutes. The temperature of the surrounding is ____.

Consider two hot bodies and which have temperatures and respectively at . The temperature of the surroundings is . The ratio of the respective rates of cooling and of these two bodies at is ____.

Newton's law of cooling is a special case of ____.

Stefan's law

Kirchhoff's law

Wein’s law

Planck's law

Equal masses of two liquids are filled in two similar calorimeters. The rates of cooling will ____.

depend on the nature of the liquids

depend on the specific heats of liquids

be same for both the liquids

depend on the mass of the liquids

16

8

4

2

Star A has radius r surface temperature T while star B has radius 4r and surface temperature. The ratio of the power of two starts, PA : PB is ____.

16 : 1

1 : 16

1 : 1

1 : 4

Suppose the sun expands so that its radius becomes 100 times its present radius and its surface temperature becomes half of its present value. The total energy emitted by it then will increase by a factor of ____.

104

625

256

16

If the temperature of the sun were to be increased from T to 2T and its radius from R to 2R, then the ratio of the radiant energy received on the earth to what it was previously is?

4

16

32

64

At 127o C radiates energy is 2.7 ( 10-3 J/s. At what temperature radiated energy is 4.32 ( 10 6 J/s?

400 K

4000 K

80000 K

40000 K

If the initial temperatures of metallic sphere and disc, of the same mass, radius and nature are equal, then the ratio of their rate of cooling in same environment is ____.

1 : 4

4 : 1

1 : 2

2 : 1

A black body radiates energy at the rate of 1 ( 105 J / s (m2 at temperature of 227o C. The temperature to which it must be heated so that it radiates energy at rate of 1 ( 109J/sm2 is ____.

5000 K

5000 oC

500 K

500 oC

The temperature of the body is increased from –73 o C to 327 o C; the ratio of energy emitted per second is ____.

1 : 3

1 : 81

1: 27

1 : 9

Two spherical black bodies of radii and and with surface temperature and respectively radiate the same power. Then the ratio of and is ____.

Temperature of a black body increases from, the initial energy possessed is 2 KJ, what is its final energy?

32 KJ

320 KJ

1200 KJ

None of the above

The original temperature of a black body is The temperature at which this black body must be raised so as to double the total radiant energy, is ____.

971 K

1190 K

2001 K

1458 K

Two black metallic spheres of radius 4m, at 2000 K and 1m at 4000 K will have ratio of energy radiation as ____.

1 : 1

4 : 1

1 : 4

2 : 1

The energy spectrum of a black body exhibits a maximum around a wavelength. The temperature of the black body is now changed such that the energy is maximum around a wavelength .The power radiated by the black body will now increase by a factor of ____.

A black body is at a temperature 300 K. It emits energy at a rate, which is proportional to ____.

The spectral energy distribution of star is maximum at twice temperature as that of sun. The total energy radiated by star is ____.

twice as that of the sun

same as that of the sun

sixteen times as that of the sun

one sixteenth of sun

Hot water cools from to in the first 10 minutes and to 42° in the next 10 minutes. The temperature of the surrounding is ____.

Consider two hot bodies and which have temperatures and respectively at . The temperature of the surroundings is . The ratio of the respective rates of cooling and of these two bodies at is ____.

Newton's law of cooling is a special case of ____.

Stefan's law

Kirchhoff's law

Wein’s law

Planck's law

Equal masses of two liquids are filled in two similar calorimeters. The rates of cooling will ____.

depend on the nature of the liquids

depend on the specific heats of liquids

be same for both the liquids

depend on the mass of the liquids

This is Thermodynamic test of Physics

**
XII_Physics_Electromagnetic Induction_7**

10 Questions
| 408 Attempts

**
XII_Physics_Electromagnetic Induction_6**

10 Questions
| 459 Attempts

**
XII_Physics_Electromagnetic Induction_5**

10 Questions
| 204 Attempts

Price:$175

Price:$100

**
PHYSICAL CHEMISTRY [Chapter 4: Thermodynamics]**

Price:$27.27274