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A plank is resting on a horizontal groun...

A plank is resting on a horizontal ground in the northern hemisphere of the Earth at a `45^(@)` latitude. Let the angular speed of the Earth be `omega` and its radius `r_e`. The magnitude of the frictional force on the plank will be

A

`mr_eomega^2`

B

`(mr_eomega^2)/(sqrt2)`

C

`(mr_eomega^2)/2`

D

Zero

Text Solution

Verified by Experts

The correct Answer is:
C
`F_rmomega^2Rcos45^(@)`
where `r_e=Rcos45^(@)`
`F_r=(momega^2r_e)/2`
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