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A wet open umbrella is held verticle and...

A wet open umbrella is held verticle and whirled about the handle at a uniform rate of 21 rev in 44 s. If the rim of the umbrella is a circle of 1 m in diameter and the hight of the rim above the floor is `4.9` m. The locus of the drop on the floor is a circle of radius

A

`sqrt(2.5) m`

B

1 m

C

3 mg

D

`1.5` m

Text Solution

Verified by Experts

The correct Answer is:
A
`v=sqrt(2a_(t)s)=sqrt(2a_(t)(piR))`

`therefore" "a_(n)=(v^(2))/(R)=2pia_(t)`
or `(a_(n))/(a_(t))=2pirArrtantheta=(a_(n))/(a_(t))=2pi`
`therefore" "theta=tan^(-1)(2pi)`
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