Question

If we double the mass of a body.Then the change in kinetic energy of the body will be?

Answer 1

the kinetic energy became half

Answer 2

let the mass of the body be m.

so we have,
KE = 1/2 mv^2 .......(1)
now, when mass is doubled then, we have.

KE = 1/2×2m×v^2 = mv^2 .......(2)

so on taking ratios of eqn (1) and (2), we have,

so KE also changes, it becomes half.

hope it helps...