The mass of car 2 is twice the mass of car 1. if both cars have the same velocity, how does the kinetic energy of car 2 compare to car 1? car 2 has four times the kinetic energy. car 2 has twice the kinetic energy. both cars have the same kinetic energy. both cars increase in kinetic energy if they slow down.

m₁ = mass of car 1  = m

m₂ = mass of car 2 = 2 m

v₁ = speed of car 1 = v₂ = speed of car 2 = v

Kinetic energy of car 1 is given as

KE₁ = (0.5) m₁ v₁²

KE₁ = (0.5) m v²                                              eq-1

Kinetic energy of car 2 is given as

KE₂ = (0.5) m₂ v₂²

KE₂ = (0.5) (2m) (v)²    

KE₂ = 2 (0.5) m v²          

Using eq-1

KE₂ = 2 KE₁

hence the correct choice is

Car 2 has twice the kinetic energy.