A black body radiates heat energy at the rate of 2 × 105 J/s/m2 at a temperature of 127°C. The temperature of black body at which the rate of radiation is 32 × 105 J/s/m2 is
527°C
273°C
873°C
927°C
A black body has maximum wavelength λm at 2000 K. Its corresponding wavelength at 3000 K will be
If the temperature of the sun is doubled, the rate of energy received on earth will be increased by a factor of
2
4
8
16
What is the difference between the two principal specific heats of 1 g of helium gas at S.T.P. ? Given molecular weight of helium = 4 and J=4.186 J cal-1 and R=8.31 J mol-1 K-1 .
0.586 cal g-1 K-1
0.496 cal g-1 K-1
0.782 cal g-1 K-1
0.576 cal g-1 K-1
The volume of a liquid is 830 m3 at 30o C and it is 850 m3 at 90o C. The coefficient of volume expansion of the liquid is
During constant temperature, we feel colder on the day when the relative humidity is
85%
60%
50%
25%
Which of the following has the highest specific heat ?
copper
hydrogen
water
silver
An ungraduated thermometer of uniform bore is attached to a centimetre scale and is found to read 10.3 cm in melting ice, 26.8 cm in boiling water and 6.5 cm. in freezing mixture. The temperature of the freezing mixture will be :
-23.003o C
-23.03o C
-23.3o C
-23.33o C
Heat capacity of a body is infinite. It means
heat is given out
heat is taken in
no change in temperature whether heat is taken in or given out
All of these
A person weighing 60 kg taken in 2000 kcal diet in a day. If this energy were to be used in heating the person without any losses, what would be his rise in temperature ? (sp. heat of human body is 0.83 cal/gm/o C )
40.16o C
44.23o C
49.99o C
47.23o C
