A 40 kg dog is sitting on top of a hillside and has a potential energy of 1,568 J. What is the height of the hillside? (Formula: PE = mgh) 3.9 m
4.0 m
39.2 m
40.0 m

Abumper car with a mass of 250 kg is traveling at a speed of 4 m/s. this bumper car collides and sticks to a second bumper car with a mass of 250 kg, which is initially at rest. what is the final speed of these two bumper cars after the collision, assuming they remain stuck together?

Due in 40 explain in terms of frame of reference if you’re inside a moving train everything on the outside can seem to be moving

What practical value did astronomy offer to ancient civilizations?