A car is accelerated on a lavelled road and attains a velocity 4 times of its initial velocity. In this process, the potential energy of the car

Options

A. does not change
B. becomes twice to that of initial
C. becomes 4 times that of initial
D. becomes 16 times that of initial

Answer

A

Explanation

Potential energy of the car don't change
and kinetic energy changes by as follows
Let, initial velocity = u
`:."Kinetic energy "K_(1)=(1)/(2)m u^(2).....(i)`
Given, after sometime velocity become 4 times of its initial velocity
i.e., final velocity (v)=4u
Now, put v = 4u, in Eq. (i), we get
Kinetic energy `=(1)/(2)m(4u)^(2)`
`=(1)/(2)m16u^(2)`
`K_(2)=16(1)/(2)m u^(2)`
From Eq. (i) `K_(2)=16K_(1)`
So in this process, the kinetic energy of car becomes 16 times that of initial energy.