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CBSE Class 9 Answered

Why only cos titta is used in work why other trigonometry identities are not used???   
Asked by kruthikalakshmim | 21 Oct, 2020, 06:02: PM
answered-by-expert Expert Answer
When a force acting on an object and the displacement is in the direction of force or non-zero resolved component of force
is possible along the direction of displacement , then work is said to be done. 
 
If direction of force and displacement are not in same direction , then resolved component of force F along the direction of
displacement is ( F cosθ ), where θ is the angle between direction of force and displacement.
 
Workdone = ( F cosθ ) × d
 
where d is displacement of object due to the action of force F.
 
If force and displacement are in same direction , then θ = 0 and cosθ =1 ,  workdone = F × d
Answered by Thiyagarajan K | 28 Oct, 2020, 04:44: PM

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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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