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
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
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
Wien's law states that :
T + λm = constant
λm T= constant
λm/T = constant
T4/ λm = constant
During constant temperature, we feel colder on the day when the relative humidity is
85%
60%
50%
25%
A sphere is at a temperature of 600K. Its cooling rate is R' in an external environment of 200 K. If temperature falls to 400 K, then cooling rate R' will be
3R/16
16R/3
9R/27
none of these
A copper block of mass 2.5 kg is heated in a furnace to a temperature of 500o C and then placed on a large ice block. The maximum amount of ice that can melt is :(sp.heat of Cu = 0.39 J/gm/o C and heat of diffusion of water = 335 J/gm)
1.53 kg
1.50 kg
1.55 kg
1.6 kg
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
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
A thermometer has wrong calibration. It reads the melting point of ice as - 10o C, the temperature of boiling point of water on this scale is :
-20o C
-40o C
-10o C
-10.7o C