Answer:
Since the KE is proportional to velocity squared, if you increase the KE by a factor of
2
, you increase
v
by a factor of
2
2
=
4
Detailed explanation :
25
=
0.5
⋅
m
⋅
(
5
2
)
Find
m
:
25
=
25
m
2
m
=
2
Hence the new KE:
KE
=
0.5
⋅
2
⋅
10
2
KE
=
100
J