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A particle moves from a point (-2hat(i) ...

A particle moves from a point `(-2hat(i) +5hat(j)) "to" (4 hat(j) +3 hat(k))` .When a force of `(4hat(i) +3hat(j))N ` is applied .How much work has been by the force ?

A

5 J

B

2J

C

8 J

D

11 J

Text Solution

Verified by Experts

The correct Answer is:
A
`W = vec(F ) . d vec(s) `
`d vec(s) = (4 hat(j) +3 hat(k)) - (-2hat(i) + 5 hat(j))`
`= + 2 hat(i) - hat(j) =3 hat(k)`
` :. W = (4hat(i) +3hat(j)).(2hat(i)-hat(j) +3hat(k))`
` = 8-3 +0`
` :. W = 5J `
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