A car braked with the constant deceleration of 30 ft s2 pro
     A car braked with the constant deceleration of 30 ft / s2, producing skid marks measuring 135 ft before coming to stop,  How fast was the car traveling when the brakes were first applied? ,  The speed limit is 55 mi/hr, Should the driver get a ticket? 
  
  Solution
a = 32ft/s^2
 s = 135 ft
v2 = u2 + 2as (third equation of motion)
=> v2 = 2*32*135
=> v= 92.95ft/s
b) 1ft/s = 0.6818 mi/hr
v = 0.6818*92.95 = 63.37mi/hr > 55mi/hr
hence yes should be given a ticket

