(c) the carpet is a better conductor of heat than the stone
   (d) the human body maintains a constant temperature
Ans: (b)
118. A bolometer is used to measure
   (a) the quantity of heat energy in a body
   (b) thermal radiations quantitatively
   (c) high temperature
   (d) the intensity of sound
Ans: (b)
119. Water has maximum density at
   (a) 0° C
   (b) -15° C
   (c) 4° C
   (d) 15° C
Ans: (c)
120. Body A is kept in contact with body B. Heat will flow from A to B if
   (a) the heat content of A is greater than that of B
   (b) the temperature of A is greater than that of B
   (c) the specific heat of A is greater than that of B
   (d) the specific heat of B is greater than that of A
Ans: (b)
121. Air escaping rapidly from a narrow orifice in an inflated tyre feels cool
   because
   (a) the speed with which it escapes cools it down
   (b) of the higher temperature of the surroundings
   (c) of sudden expansion causing loss of internal energy
   (d) there is no real fall in temperature
Ans: (c)
122. The atmosphere gets heated up mainly by
   (a) direct sun"s rays
   (b) radiation from earth"s surface
   (c) radiogenic heat (resulting from radioactive decay)
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