Question

when work is zero than angle between force and direction of displacement is .....degree

Answer 1

90 degree is the angle between the
force and direction of displacement

Answer 2

Work done is said to be done on an object when a force F acts on the object and object moves through a displacement S.
Wordone=W=Fxd
If force acts at an angle with d then ,
W= FdCOSθ

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Work done will be zero if Force acting is zero.
Displacement is zero or
Angle between F and d is 90 or 270.
As cos90=cos270=0
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