A ball has 10 Joules of kinetic energy as it reaches the bottom of the hill. Approximately how much potential energy did the ball have at the top of the hill?

How does an observation about an object differ from an inference about that object

Two point charges are separated by a certain distance. how does the strength of the electric field produced by the first charge, at the position of the second charge, change if the second charge is doubled? a. the field does not change b. the field strength decreases by half. c. the field strength doubles d. the field strength quadruples

What is similar between metals and suspensions