Question

A 1451 kg car is traveling at 48.0 km/h. Compared to 48.0 km/h, what would be the fraction of energy the car would have if it were traveling at 24.0 km/h.

Answer 1

Ke = (1/2)(m)(v^2)
Ke = (1/2)(1451kg)(48^2)
Ke = 1,671,552 joules

Ke = (1/2)(1451)(24^2)
Ke = 417,888

1/4th the energy

Answer 2

We know, kinetic energy is directly proportional to the square of velocity, So, if kinetic energy is halved it's velocity will reduce to its 1/4th value

In short, Your Answer would be 1/4

Hope this helps!