Correct answer: option C − It becomes nine times the initial value.
Solution:
Kinetic energy of an object, K=12mv2, where m is the mass of the object and v is the velocity of the object.
Given: the initial velocity is u.
So, the initial kinetic energy Ki=12mu2
If the velocity of the object becomes thrice its initial velocity, then, v=3u.
The new kinetic energy is:
Kf=12m(3u)2=9×12mu2=9Ki
Therefore, the kinetic energy becomes 9 times the initial value.