If momentum of a car is increased by 20% then its K.E is increased by ______?
If momentum of a car is increased by 20% then its K.E is increased by ______?
Explanation
Kinetic energy (K) is related to momentum (p) by K = p² / 2m. If momentum increases by 20%, the new momentum p' = 1.2p.
The new kinetic energy K' = (p')² / 2m = (1.2p)² / 2m = 1.44p² / 2m = 1.44K.
The percentage increase in K.E is ((K' - K) / K) × 100 = ((1.44K - K) / K) × 100 = 44%.