A rock is elevated such that it has 100 J of gravitational potential energy. After it is released, it falls to a height where it only has 30 J of gravitational potential energy. If there is no
friction then its kinetic energy would be?
A. 30j. B. 70j. C.100j

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?

Work out sian speed for the first 30 minutes of her journey. give your answer in km/h.

I'm thinking it's 2 you are asked to explain the earth's magnetic field. which is the best reply? 1. the earth's magnetic south is similar to the north pole of a magnet. 2. the earth's core has a strong magnetic charge similar to the south pole of a magnet. 3. the earth's geomagnetic south is similar to the south pole of a magnet. 4. the earth's magnetic charge is not centered at either pole; it varies based on location.