Question

The coefficient of friction between the tyres and road is $0.4$. The minimum distance covered before attaining a speed of $8{\text{ms}}^{-1}$ starting from rest is nearly $(g=10m/s^2)$

• A. 8.0 m
• B. 4.0 m
• C. 10.0 m
• D. 16.0 m

Answer 1

The correct option is A 8.0 m

Acceleration $a=\frac{\mu mg}{m}=\mu g=4m/s^2$
From equation $v^2-u^2=2as$
$8^2-0^2=2\left(4\right)s$
$\therefore s=8.0m$