Power from a car engine is the power of a bicycle because a car engine does the same amount of work in time. Raul and Katrina equally shared a frozen lunch but heated each portion in two different microwaves. Katrina’s lunch was warm in one minute while Raul’s lunch took two minutes. The power used by Raul’s microwave must be the power used by Katrina’s because his microwave took time to do the same amount of work.

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.