A `20 kg` block is originally at rest on a horizontal surface for which the coefficient of friction is `0.6`. A horizontal force `F` is applied such that it varies with time as shown in the figure (a) & (b). If the speed of the block after `10 s` is `8v` then find `v`. ( Take `g=10m//s^(2)`)

Answer

3

Explanation

`F - mu mg = m(dv)/(dt)`
`"m" int_(0)^(v) dv = int_(3)^(10)dt - mu mg int_(3)^(10) dt `
`implies 20 v = 480 implies v = 24`