One kilogram of ice at C is mixed with one kilogram of water at 80. The final temperature of the mixture is (Take: Specific heat of water = 4200 J , Latent heat of ice = 336 kJ )
(1) C (2)
(3) (4)
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The fastest mode of heat transfer is
1. Conduction
2. Radiation
3. Convection
4. all are equally fast
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A temperature of 100 oF (Fahrenheit scale) is equal to T K (Kelvin scale). The value of T is:
1. 310.9
2. 37.8
3. 100
4. 122.4
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A black body at temperature 300K radiates heat at the rate E. If its temperature is increased by 600K, the rate of radiation will increase to -
1. 16E
2. 64E
3. 81E
4. 256E
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A body cools down from in 5 minutes. The temperature of the body will fall from in a time:
1. less than 5 minutes.
2. equal to 5 minutes.
3. more than 5 minutes.
4. can't say anything like the temperature of surroundings is not known.
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If is the wavelength, corresponding to which the radiant intensity of a block is maximum and its absolute temperature is T. Which of the following graph correctly represents the variation of with T.
1.
2.
3.
4.
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Heat capacity is equal to the product of:
1. mass and gas constant
2. mass and specific heat
3. latent heat and volume of water
4. mass and Avogadro number
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When a block of iron floats in Hg at , a fraction of its volumen= is submerged, while at temperature of a fraction is seen to be submersed. If the coefficient of volume expansion of iron is and that of mercury is , then the ratio can be expressed as:
1.
2.
3.
4.
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Hot water cools from 60 to 50 in first 10 minutes and from 50 to 42 in next 10 minutes. The temperature of surrounding is :
1.
2.
3.
4.
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A pendulum clock runs fast by 5 sec per day at 20 oC and goes slow by 10 sec/day at 35 oC. It shows the correct time at a temperature of:
1. 27.5 oC
2. 25 oC
3. 30 oC
4. 33 oC
Difficulty Level: