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    (c)   They would generate cold air to               (b)   Thick clothes act as conductors to
                                   keep the rooms chilled.                             pull the heat away from the skin.

                                (d)   They would make the house weigh               (c)   Loose clothes allow air to circulate
                                   less because the air is removed.                    (convection) and carry away body
                     10.  Why do people living in desert climates often                heat, while the white color reflects
                         wear loose, flowing white robes instead of tight-             solar radiation.
                         fitting white T-shirts?   (Abstract Thinking)
                                                                                    (d)   There is no scientific reason; it is
                                (a)   Tight clothes are said to reflect the            simply a cultural preference.
                                   Sun’s  radiation  more  effectively,
                                   reducing  heat  absorption  by  the
                                   body.

                                       You have a black iron pot and a shiny silver pot, both filled with boiling water
                                       at 100°C. You place them in a cool room. Which pot will cool down to room
                                       temperature first?

                                             (a)   The shiny silver pot, because silver is a better conductor than iron.

                                             (b)   The shiny pot, because it reflects the coldness of the room into the
                                                 water.

                                             (c)   Both will cool at the exact same rate because they start at the same
                                                 temperature.

                                             (d)   The black  iron  pot,  because  dark-colored  surfaces  are  better
                                                 "emitters" (givers) of heat radiation than shiny surfaces.

                                                                                           Heat Transfer in Nature    77

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