Sketch a picture showing the difference between tensional extensional and compression forces

How much force must a locomotive exert on a 12840-kg boxcar to make it accelerate forward at 0.490 m/s2?

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

True or false: the cycle of seasons on the earth is caused by the tilt of the earth on its axis toward and away from the sun.