PLEASE HELP! A 10.0-kilogram ball rolling along a flat surface starts up a hill. If the ball reaches a height of 1.0 meters, what was its initial speed?

What is the relationship between the wavelength of a wave and it's energy?

If a refrigerator is a heat pump that follows the first law of thermodynamics, how much heat was removed from food inside of the refrigerator if it released 380j of energy to the room?

Ahanging spring stretches by 35.0 cm when an object of mass 450 g is hung on it at rest. in this situation, we define its position as x = 0. the object is pulled down an additional 18.0 cm and released from rest to oscillate without friction. what is its position x at a moment 84.4 s later? express your answer in cm.