Question

Assertion (A): The kinetic energy of a body is quadrupled, when its velocity is doubled
Reason (R) : Kinetic energy is proportional to square of velocity

• A. A and R are correct and R is the correct explanation of A
• B. A and R are correct and R is not the correct explanation A
• C. A is true and R is false
• D. A is false and R is true

Answer 1

Answer: (A)

A and R are correct and R is the correct explanation of A

when velocity is doubled
$K=$$1/2\left(m{v}^2\right)$ bceomes $K^{\prime }=$$1/2\left(m\right(2v{)}^2)$ = $4\left[1/2\right(m{v}^2\left)\right]$
so $KE$ becomes four times