The block of mass m intially at x=0 is acted upon by a horizontal force at any position x is given as `F=a-bx^(2)`(where `agtmumg`), as shown in the figure. The co-efficient of friction between the surface of contanct is `mu`. The net work done on the block is zero, if the block travels is distance ?

Options

A. `sqrt((3(b-mumg))/a)`
B. `sqrt((3(a-mumg))/b)`
C. `sqrt((a mu mg)/b)`
D. none of these

Answer

B

Explanation

`W_(1)+W_(p)=-mumgx+int_(0)^(x)(a-bx^(2))dx`
`0=(-mumg+a)x-(bx^(2))/3`
`rArr x=sqrt((3(a-mumg))/b)`