Question

If the velocity of a body is increased 3 times what happens to its kinetic energy

Answer 1

Kinetic energy is proportional to mass times velocity squared. Momentum can be increased by increasing mass and or velocity so that the product increases three times.

Answer 2

KE=1/2 mv^2

new KE=1/2 m(3v)^2

=1/2 m9v^2

KE / newKE= 1/9

so KE becomes nine times