• # question_answer An automobile, travelling at $40km/h$, can be stopped at a distance of $40m$by applying brakes. If the same automobile is travelling at $80km/h$, the minimum stopping distance, in metres, is (assume no skidding) [JEE Online 15-04-2018] A) $75m$ B) $160m$ C) $100m$ D) $150m$

 [b] Since stopping distance, $s=\frac{{{v}^{2}}}{2a}$ For case $1,40=\frac{{{(40\times \frac{5}{18})}^{2}}}{2a}..........(1)$ For case 2, $s=\frac{{{(80\times \frac{5}{18})}^{2}}}{2a}...........(2)$ From (1) and (2), $s=160m$