Answer
Kinetic energy: x4
Momentum: x2
Work Step by Step
As $K.E=\frac{1}{2}mv^2$
According to given condition
$K.E^{\prime}=\frac{1}{2}m(2v^2)=4(\frac{1}{2}mv^2)=4K.E$
Thus, kinetic energy increases by a factor of 4.
Momentum is given as
$p=mv$
according to given condition
$p^{\prime}=m(2v)=2(mv)=2p$
Thus, momentum doubles.
