A gas is compressed from an initial volume of 5.65 L to a final volume of 1.21 L by an external pressure of 1.00 atm. During the compression, the gas releases 128 J of heat. What is the change in internal energy of the gas? Express your answer to three significant figures.

Oxygen and hydrogen gas are at the same temperature t. what is the ratio of kinetic energies of oxygen molecule and hydrogen molecule if oxygen is 16 times heavier than hydrogen.

Astone is dropped from a cliff and falls 9.44 meters. what is the speed of the stone when it reaches the ground? a. 13.6 m/sec b. 1.39 m/sec c. 185 m/sec d. 9.80 m/sec

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.