In: Physics
In an elastic collision, the linear momentum and the energy both are conserved.
The initial momentum of the system is
The initial energy of the system is
The final momentum of the system is
The final energy of the system is
The conservation of momentum and energy gives us
Putting the value of v1
The solutions to this quadratic equation are
and
The later solution (v2 = 1.5) is its initial value. So, the solution we are interested is v2 = 2.5 m/s.
So, the solution is
Putting this value in equation
So, the answer is