Question

A Thousand kilogram vehicle moving with a speed of 20 metre per second is brought to rest in a distance of 50 M find the acceleration and calculate the unbalanced force acting on the vehicle and the actual force applied by the applied by the break maybe slightly less than the calculated and give reason

Answer 1

Data:  mass of the body = 1,000 kg
          Initial velocity (u) = 20 m/s
          Final velocity (v) = 0 m/s
           Displacement (S) = 50 m
              Force acting (F) =?
Solution: 

We know that F = ma and      2as=  v2 - u2  ⇒ 2 × a × 50 m = 02 - 202

a= -4 m/s2 now F = ma ⇒F = 1,000 × -4 = -4,0000N

Note:  Negative symbol represents The opposit direction to the displacement.