A car moving with a speed of `50 km h^(-1)` can be stopped by brakes after atleast 6 m. If the same car is moving at a speed of `100 km h^(-1)` the minimum stopping distance is

Options

A. ` 12m`
B. ` 18m`
C. `24 m`
D. ` 6 m`

Answer

C

Explanation

Assuming constant retardation:
using ` v^(2) =u^(2) +2as rArr 0=u^(2)-2as or s= (u^(2))/(2a) or (s_1)/(s_2)=(u_1^(2))/(u_2^(2))`
` ( 6)/(s_2) =((50)/(100))^(2) rArr s_2 =24m`