Help please quick A 30 kg cart moving at 10 m/s collides head on with a 20 kg cart. After the collision both carts come to a stop. What was the original speed of the 20 kg cart?

An object's buoyant force and weight mean the same thing.a. trueb. false

Balloon a has charge q, and identical mass balloon b has charge 10q. you hang them from threads near each other. choose all of the statements with which you agree. check all that apply. a. a and b exert the same magnitude forces on each other. b. the force that a exerts on b is 10 times the force that b exerts on a. c. the angle between the thread supporting a and the vertical is < the angle between the thread supporting b and the vertical. d. the force that a exerts on b is 1/10 the force that b exerts on a.

Holes drilled several kilometers into earth’s crust provide direct evidence about earth’s interior in the form of