A boy and his skateboard have a combined mass of 41.3 kg. What is the combined momentum of the boy and his skateboard if they are traveling at 8.50m/s ?

How is sound energy produced a. vibrating objects b. objects being heated c. temperature differences d. stationary objects

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final