An automobile travellingat `40 km//h`, can be stopped at distance of 40 m by applying brakes. If the same autombile is travelling at`80 km//h`, the minimum stopping distance, in metres is (assume no skidding) :

Options

A. 75m
B. 160m
C. 100m
D. 150m

Answer

B

Explanation

According to question `u_(1) = 40km//h, v_(1) = 0 and s_(1) = 40m`
using `v^(2) - u^(2) = 2as, 0^(2) - 40^(2) = 2a xx 40`…(i)
Again, `0^(2) - 80^(2) = 2as`
From eqn(i) and (ii) stopping distance s = 160m