//Police investigation
//refer fig. 16.9
//Let the probable speed of the car just before brakes are applied be u m/sec
//F=0.5*W
//Final velocity=0
s=60  //m
//applying work energy equation 
u=((sqrt(0.5*60*2*9.81))*60*60)/1000  //m/sec
printf("\nThe probable speed of the car just before brakes are applied is %.2f kmph",u)