A car moving with a speed of 50km/h can be stopped by brakes after at least 6m. If the same car is moving at a speed of 100km/h, the minimum stopping distance is

Using work-energy theorem, Wtotal  = ΔKi.e, work done by stopping forces should be equal to change in the kinetic energy of the car.  -Fstopping xstoppingdistance=(kfinal-kinitial)   -Fstopping x S= 0−12mv2initial ⇒-Fstopping x S =12mv2initial  As stopping force is same for both the cars, henceSαv2  initial =>Hence ,  S1S2=(v2initial)1(v2initial)2Or  6S2=(v2initial)1(v2initial)2=(50100)2⇒S2=24m