540 g of ice at 0o C is mixed with 540 g of water at 80o C. The final temperature of the mixture is
40o C
79.9o C
80o C
0o C
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
During constant temperature, we feel colder on the day when the relative humidity is
85%
60%
50%
25%
Wien's law states that :
T + λm = constant
λm T= constant
λm/T = constant
T4/ λm = constant
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
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
Which of the following has the highest specific heat ?
copper
hydrogen
water
silver
The radiator of a car contains 20 litre of water. If the motor supplies calorie heat to it, then rise in temperature will be :
10o C
20o C
100o C
103 oC
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
