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A person throws a ball in vertical plane...

A person throws a ball in vertical plane such that velocity of ball along horizontal is `V_(x)` and along vertical is `v_(gamma)`. Coefficinet of friction between man and gound is `mu`. Necessary condition so that man always remains at rest will be (Note: the process is done in time `Deltatto0)`

A

`v_(x)gtmuv_(gamma)`

B

`v_(x)lemuv_(gamma)`

C

`v_(y)lemuv_(x)`

D

`muv_(x)lev_(y)`

Text Solution

Verified by Experts

The correct Answer is:
B

`J_(N)=mv_(y)`
`J_(f)lemuJ_(N)`
`mv_(x)lemumv_(y)implies(v_(y))/(v_(x))ge(1)/(mu)`
`muv_(y)gev_(x)`
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