Mechanical energy can be lost or gained . 机械能可以消失或者可以增生。
Heat is thereby converted into mechanical energy of the piston . 热由此转换成活塞的机械能。
An electric motor turns electrical energy into mechanical energy . 电动机把电能转换成机械能。
Every bit of mechanical energy expended reappears as heat . 所消耗的每一点机械能都再现为热能。
During the flow we manage to change some of the heat into mechanical energy . 在流传中我们设法把部分热变成机械能。
This is a process for which the principle of the conservation of mechanical energy holds . 这是一个能够应用机械能守恒原理的过程。
Under these conditions, the total mechanical energy remains constant, or is conserved . 在这种条件下，总机械能保持不变或机械能保存。
He found that a given amount of mechanical energy invariably produced the same amount of heat . 他发现一定量的机械能会恒定地产生等量的热。
In the special case in which w'is zero, the mechanical energy remains constant or is conserved . 在W’等于零的特殊情况下，机械能保持不变或称保守。
In the absence of air resistance, the only force on a projectile is its weight, and the mechanical energy of the projectile remains constant . 忽略空气阻力，作用在抛体上的力只是它的重量，因而该抛体的机械能是守恒的。
