Balls a, with a mass of 20 kg, is moving to the right at 20 m/s. at what velocity should ball b, with a mass of 40 kg, move so that they both come to standstill upon collision?

Match the words or actions and their definition. 1. the rate of doing work 2. a machine that changes motion 3. the force that is used to generate electricity 4. 550 foot-pounds per second 5. the force that makes things fall toward the earth 6. work in > work out 7. metric measurement of work 8. the product of force times distance water falling from a dam newton-meter gravity work windmill power the work principle 1 horsepower