An object with kinetic energy K explodes into two pieces, each of which moves with twice the speed of the original object.

Options

A. The final energy is 4K only if the pieces are of equal mass.
B. The final energy is 4K even if the pieces are of unequal mass.
C. The final energy is 2K only if pieces are of equal mass.
D. The final energy is 2K even if pieces are of unequal mass.

Answer

B

Explanation

`(m_(2)+m_(1))vec(v)_(0)=m_(1)xxvec(v)_(1)+m_(2)xxvec(v)_(2)`
`k_(i)=k=1/2(m_(1)+m_(2))vec(v)_(0)^(2)`
`k_(f)=1/2m_(1)xx4v_(0)^(2)+1/2 m_(2)xx4v_(0)^(2)`
`k=1/2 (m_(1)+m_(2))4v_(0)^(2)`