Question

which would have greater effect on k.e. of an object -doubling the mass r doubling velocity

Answer 1

Since Kinetic energy of a body is given by :-
K.E. = $\frac{1}{2}m{v}^{2}wheremandvarethemassandvelocityofthebody.$
Case 1 :-
When the mass is doubled, then m = 2 m

Therefore, K.E. in this case is equal to mv2
Case 2 :-
When the velocity is doubled, then v = 2v
​Therefore, K.E. in this case is equal to 2 mv^​2
Hence by doubling the velocity, the kinetic energy of the body would get double.