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An object is moving along a straight lin...

An object is moving along a straight line path from P to Q under the action of a force `vec(F)=(4 hati-3hatj+hat2k)N`. If the co-ordinate of P and Q in meters are (3,2,-1) and (2,-1,4) respectively. Then the work done by the force is

A

`-15 J`

B

`+15 J`

C

`1015 J`

D

`(4hati-3hatj+2hatk)`

Text Solution

Verified by Experts

The correct Answer is:
B
`vec(PQ)=(2-3)hati+(-1-2) hatj(4-(-1))hatk`
`vec(F).vec(PQ)=-4+9+10=15 J`
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Knowledge Check

  • An object is moving along a straight line path from P to Q under the action of force vec(F)=(4hat(i)-3hat(j)+2hat(k))N . If the co - ordinate of P & Q in metres are (3,2,-1) & (2,-1,4) respectively. Then the work done by the force is :

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    B
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    A
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