Question

How much energy must the shock absorbers of a 1200-kg car dissipate in order to damp a bounce that initially has a velocity of 0.800 m/s at the equilibrium position? Assume the car returns to its original vertical position.

a) (384 kJ)
b) (480 kJ)
c) (576 kJ)
d) (672 kJ)

Answer 1

The energy that must be dissipated by the shock absorbers of a 1200-kg car to damp a bounce with an initial velocity of 0.800 m/s is 384 J, which corresponds to the kinetic energy of the car at that velocity. The correct answer is option a) (384 J).

Step-by-step explanation:

The question is related to the energy dissipation by shock absorbers of a car. To find out how much energy must be dissipated by the shock absorbers of a 1200-kg car to damp a bounce with an initial velocity of 0.800 m/s, we use the work-energy theorem.

This theorem states that the work done by the forces on the car (in this case, the damping force of the shock absorbers) is equal to the change in kinetic energy of the car. The kinetic energy (KE) of an object with mass (m) and velocity (v) is given by the equation KE = 0.5 × m × v2.

For a car with mass m = 1200 kg and initial velocity v = 0.800 m/s, the initial kinetic energy is:

KE = 0.5 × 1200 kg × (0.800 m/s)2 = 0.5 × 1200 kg × 0.64 m2/s2 = 384 J

Therefore, the shock absorbers of the car must dissipate 384 J of energy to damp the bounce. The correct option is a) (384 J).