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W = F×d×cos? how is that possible? can you explain?

Work is actually force dot distance. 
W=F.d 
The dot means (*cos?) where ? is the angle between the force's line of action and the distance travelled. This is important because work is only done when there is a force component in the direction of motion. 
Example: 
A bellboy picks up a suitcase. Because he is exerting a force in the direction the suitcase is moving, work is done. He then caries the suitcase across the lobby at a constant speed. Although he is still applying a force to support its weight, it is at right angles to the motion, 
so no work is done on the suitcase.



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