Why is it difficult to use the law of conservation of energy to calculate the effects of a collision?
A. Energy is not conserved.
B. Energy is only conserved during inelastic collisions.
C. Energy is destroyed during a collision.
D. Energy is converted to heat during a collision.

2kg of refrigerant 134a undergoes a polytropic process in a piston-cylinder assembly from an initial state of saturated vapor at 2 bar to a final state of 12 bar, 80 degree c. a)determine the work for the process in kj. b)sketch the process on a p-v diagram.

As a pendulum bob swings back and forth several times, the maximum height it reaches becomes less and less. this is because more and more of the pendulum bob's energy is being transformed into a. heat energy b. kinetic energy c. potential energy d. kinetic energy and potential energy

Give me a example of a decomposer. explain what would happen if decomposers were absent from a forest ecosystem