The coefficient of friction between the tyres and road is 0.4. The minimum distance covered before attaining a speed of 8 `ms^(-1)` starting from rest is nearly (take, g=10 `ms^(-2)`)

Options

A. 8m
B. 4m
C. 10m
D. 16m

Answer

A

Explanation

Retardation , `a=(mumg)/(m)=mug=4ms^(-2)`
Using , `v^2=u^2+2as`
`(8)^2 = (0)^2 + 2(4)(s)`
`therefore` s=8m