1.

A particle is moving in a circular path of radius a under the action of an attractive potential U = -k/(2r^(2)) .Its energy is

Answer»

`k/(4a^(2))`
`k/(2a^(2))`
zero
`-3/2 k(a^(2))`

Solution :`U = k/(2r^(2)) "" ` ….(1)
` :. (dU)/(dr) = k/2 (-2r^(-3) (dr)/(dr))`
` :. F = k/(r^(3))`
Now particle is moving in CIRCULAR path of radius a instead of RADIUSR , the CENTRIPETAL force
`(mv^(2))/a = k/(a^(3)) "" [ :. r =a]`
` :. 1/2 mv^(2) =k/(2a^(2))`
` :. k = k/(2a^(2))""...(2)`
` :. "Total energy " = U+k`
` = - k/(2a^(2) +k/(2a^(2))`
`[ :. " from equ .(1) and (2) r =1"] `
= 0


Discussion

No Comment Found