Question

If you double your speed, your kinetic energy will increase by: A. Double B. Triple C. Quadruple D. Quintuple

Answer 1

Answer:

C. Quadruple

Explanation:

$m$ = mass

$v_{i}$ = initial speed = $v$

$K_{i}$ = initial kinetic energy

Initial kinetic energy is given as

$K_{i} = (0.5) m v_{i}^{2}\\K_{i} = (0.5) m v^{2}$

$v_{f}$ = Final speed = $2 v$

Final kinetic energy is given as

$K_{f} = (0.5) m v_{f}^{2}\\K_{f} = (0.5) m (2v)^{2}\\K_{f} = 4 (0.5) m v^{2}\\K_{f} = 4 K_{i}$

Hence the kinetic energy is quadruple