A 220kg refrigerator is dropped from the top of a 42m tall building. 1. What is the refrigerators potential energy just before it is released?
2. What is the refrigerators kinetic energy just before it's released?
3. What is the refrigerators potential energy just before it strikes the ground?
4. What is the refrigerators kinetic energy just before it strikes the ground?
5. What is the refrigerators speed just before it strikes the ground?

What happens in a global convection cell

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.

What is the moment of inertia i of this assembly about the axis through which it is pivoted? express the moment of inertia in terms of mr