When the speed of a car is halved, its kinetic energy is
A
doubled
B
quartered
C
halved
D
quadrupled
Verified Correct Answer: B.
Physical Principles & Numerical Solution
Given \(K_{1}\) = \(\frac{mv^{2}}{2}\).
When v is halved, we have
\(K_{2}\) = \(\frac{m\times (\frac{v}{2})^{2}}{2}\)
= \(\frac{K_{1}}{4}\)
Hence, the initial kinetic energy is quartered.
Source: Myschool Past Questions Archive (Record #49798)