113. The mode of travel of heat energy from the sun across the empty space
   beyond the earth"s atmosphere is known as
   (a) conduction
   (b) convection
   (c) radiation
   (d) absorption
Ans: (c)
114. Tea pots are highly polished
   (a) so that they may reflect thermal radiation from outside and minimise such
       radiation from them
   (b) so that they may absorb all radiation from outside
   (c) to make them attractive to look at
   (d) because they take high polish
Ans: (a)
115. A cup of hot coffee is placed on a metal table in a room. By which of the
   following methods does it lose heat?
   (a) conduction and convection only
   (b) conduction and radiation only
   (c) convection and radiation only
   (d) conduction, convection and radiation
Ans: (d)
116. Drinks kept in a vacuum flask remain hot or cold as the case may be for a
   long time because
   (a) both walls are silvered on the vacuum side
   (b) there is vacuum between the double walls
   (c) the cork is a poor conductor of heat
   (d) of all the above
Ans: (d)
117. A stone floor feels cold to the bare feet but a carpet on the same floor
   feels warm. This is because
   (a) the floor and carpet are at different temperatures
   (b) the stone conveys the heat away from the feet more rapidly than the