Ratio of final kinetic energy to initial kinetic energy is 16.
Step-by-step explanation:
Kinetic energy , KE = 0.5mv²
Here car speeds up to four times the initial speed, we need to find ratio of final kinetic energy to initial kinetic energy.
Final speed = 4 x Initial speed = 4v
Initial KE = 0.5mv²
Final KE = 0.5 x m x (4v)²
Final KE = 16 x 0.5 x m x v²
Final KE = 16 x Initial KE
Ratio of final kinetic energy to initial kinetic energy is 16.