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Let a force F be acting on a body free t...

Let a force F be acting on a body free to rotate about a point O and let r the position vector of ant point P on the line of aciton of the force. Then torque `(tau)` of this force abot point O is defined as ` tau = rxxF` Given, `F = (2hati + 3hatj - hatk)N and r = (hati- hatj+6hatk)m` Find the torque of this force.

A

`(-16hati +13hatj+7hatk)N-m`

B

`(-17hati -13hatj-5hatk)N-m`

C

`(-17hati +13hatj+5hatk)N-m`

D

`(-16hati +11hatj+15hatk)N-m`

Text Solution

Verified by Experts

The correct Answer is:
C
Given ,`F=(2hati+3hatj-hatk)N and r+(hati-hatj+6hatk)m`
`therefore "Torqure"t=rxxF=|underset(2 ,3,-1)underset(1,-1,6)hati,hatj,hatk|`
`hati (1-18)+hatj(12+1)+hatk(3+2)`
`or t=(-17hati +13hatj+5hatk)N-m`
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