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A bead slides on a frictoinless straingh...

A bead slides on a frictoinless strainght rod fixed between points `A` and `B` of a vertical circular loop of radius as shown in the figure. Line `BC` is a vertical diameter. Denoting acceleration due to gravity by `g`, which of the following is correct expression for the time taken by the bead to slide from `A` to `B`

A

`sqrt((4r)/(g))`

B

`sqrt((4r)/(gcostheta))`

C

`sqrt((4rtantheta)/(g))`

D

`sqrt((4rcottheta)/(g))`

Text Solution

Verified by Experts

The correct Answer is:
A

`a=gcostheta,L_(AB)=2rcostheta=(1)/(2)at^(2)rArrt=sqrt((4r)/(g))`
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