Compare the rate of heat transfer by radiation for two objects, the first one has the temperature Ts1= 25 degree Celsius and the second is kept at temperature Ts2 = 40 degree Celsius. Suppose they are made of identical material (e1=e2) and have the same area participating in radiation (Ar1=Ar2). The Surrounding temperature Tr= 25 degree Celsius.

Complete these sentences. if a roller coaster train has a potential energy of 1,500 j and a kinetic energy of 500 j as it starts to travel downhill, its total energy isj. once the roller coaster train gets closer to the bottom of the hill, its kinetic energy increases to 1,100 j, and its potential energy decreases to j. when the train reaches the bottom of the track and is traveling along the ground, its kinetic energy isj.