A 1,500 kg car’s speed changes from 30 m/s to 15 m/s after the brakes are applied. Calculate the work done onto the car from the brakes.

All the simple machines make work easier to do by changing the or of a force. a. size; type b. work; type c. size; direction d. type; direction

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct

Gasoline comes from petroleum, which is made from ancient living things. petroleum, therefore, contains a type of energy. a. heat b. nuclear c. biological d. chemical potential