Which of the following statements describes how a heat pump works?

1. the heat pump decompresses gas to warm and cool air.
2. the heat pump compresses gas to warm air and decompresses gas to cool air.
3. the heat pump compresses gas to warm and cool air.
4. the heat pump decompresses gas to warm air and compresses gas to cool air.

Can somebody explain to me how newton's 3rd law relates to momentum? ~ap physics 1

This problem has been solved! see the answera non-uniform fire escape ladder is 6.0m long whenextended to the icy alley below. it is held at the top by africtionless pivot, and there is neglibible frictional force fromthe icy surface at the bottom. the ladder weighs 250n, and it'scenter of gravity is 2.0m along the ladder from the bottom. amother and child of total weight 750n are on the ladder 1.5m fromthe pivot. the ladder makes an angle θ with the horizontal. find the magnitude and direction ofa) the force exerted by the icy alley on the ladderb) the force exerted by the ladder on the pivotc) do your answers in part a and b depend on the angle?

For waves in the ocean, the medium of the waves is a. air b. water c. energy d. a passing boat