If a force is applied to a mass and the mass does not move:
A. Work is done even though there is no movement of the mass
B. Work is done only if the mass moves a long way
C. Power is exerted, but no work is done
D. No work is done
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The unit of work is called the:
A. Pascal
B. Joule
C. Watt
D. Kilogram
The unit of power is called the:
A. Joule
B. Newton-metre
C. Watt
D. Metre per second
高副连接的两构件的瞬心位于( )
A. 高副接触点
B. 过高副接触点的公法线上
C. 过高副接触点的公切线上
若一对齿轮的安装中心距大于标准中心距,则要保证无侧隙啮合的齿轮传动类型是( )。
A. 零传动
B. 正传动
C. 负传动