An automobile engine has an efficiency of 19.0%. if it produces 23.0 kj of mechanical work per second, the heat rejected per second from the engine is closest to: (a) 77.0 kj (b) 81.5 kj (c)86.5 kj (d) 92.0 kj (e) 98.1 kj

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

How much force was applied to an object if was moved 2 meters and the work done on the object was 8 joules? a. 0.25 n b. 4 n c. 6 n d. 16 n

What is the magnitude of the acceleration vector which causes a particle to move from velocity −5i−2j m/s to −6i+ 7j m/s in 8 seconds. answer in m/s.