a 2 100 kg car drives east towards a 55 kg shopping cart that has the velocity of .50 m/s west. The two objects collide, giving the car a final velocity of 6.31m/s east and the shopping cart a velocity of 13.5 m/s east. What was the initial velocity of the car?

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.