Which of the following is an example of a reversible process? A hand pump is rapidly compressed and the pressure and temperature in the pump rise. The pump is held in position as the temperature drops to the ambient temperature. A car engine burns fuel to produce motion of the car and exhausts the 140°C waste products of the combustion into the 20°C atmosphere. An ice cube at 0°C melts while in a water bath at 0°C. A stick of dynamite explodes. A high pressure air tank at room temperature has its valve opened and the gas in the tank rushes out until the pressure in the tank is equal to atmospheric pressure.

The best answer to the question: Which of the following is an example of a reversible process, would be: An ice cube at 0° melts while in a water bath at 0°.

Explanation:

A reversible process in physics is defined as a process, be it of physical, or chemical quality, that can be reversed, without much effort, or without exernal factors having to effect effort on the system. There is very little changes in the systems to produce this reversible effect, and just as the system can move in one direction, it can easily return to how it was before. One example of a reversible process is the transfer of heat from one system to another, without having outside forces, or extra forces and factors, to produce the change, and with very little effort, or energy exchange, the process can be reverted. In this case, the cube and the water, who are at the same temperature, exchange heat, thus, the cube melts. This process of heat transfer from the cube to the water is not altered by external factors, but it is a natural process, and it can be reverted (the transfer of heat, not necessarily the change in appearance, or state), without much effort.