Question

Suppose a child drives a bumper car head on into the side rail, which exerts a force of 3400 N on the car for 0.400 s. (Assume the initial velocity is in the positive direction.) (a) What impulse (in kg · m/s) is imparted by this force? (Indicate the direction with the sign of your answer.) kg · m/s (b) Find the final velocity (in m/s) of the bumper car if its initial velocity was 3.50 m/s and the car plus driver have a mass of 200 kg. You may neglect friction between the car and floor. (Indicate the direction with the sign of your answer.) m/s

Answer 1

Answer:

a)   I = -1360 N s   b)  $v_{f}$ = -3.3 m / s

Explanation:

a) The expression of the impulse is

      I = F t = Δp

The force applied by the rail is in the opposite direction to the movement, so it is negative

     I = -3400 0.400

     I = -1360 N s

b) We use the momentum relationship with the moment

    I = ΔP

    I = m $v_{f}$- mv₀

   $v_{f}$ = (I + m v₀) / m

   $v_{f}$ = (-1360 + 200 3.5) / 200

   $v_{f}$ = -3.3 m / s