Energy that comes from the heat of the earth's core is known as:
solar energy
hydro energy
geothermal energy
wave energy

Oxygen undergoes an isentropic expansion from 120 degree c and 280 kpa absolute to 140 kpa absolute. determine the final temperature of the oxygen and the amount of work per kg of o_2 produced in the process if it is adiabatic.

Polly is pushing a box across the floor with a force of 30 n. the force of gravity is –8 n, and the normal force is 8 n. which value could describe the force of friction if polly could not move the box?

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2