A missile has been fired with an initial velocity u. If the velocity is tripled, what will be the corresponding change in its kinetic energy?
Becomes nine times the initial kinetic energy
Kinetic energy of an object, KE=12mv2, where m is the mass of the object and v is the velocity of the object.
Given: Initial velocity is u.
So, initial kinetic energy KE=12mu2
If the velocity of the object becomes thrice its initial velocity, then, v=3u.
The corresponding change in its kinetic energy is
KE′=12m(3u)2=9×12mu2=9KE
Therefore, the kinetic energy becomes 9 times the initial kinetic energy.