Reduced mass for an infinite mass and a finite mass?

[cbjewelz]

Homework Statement

We have a collision between a finite mass steel ball and an infinite mass steel wall and must find the maximum compression if we are given the mass of the ball, the initial speed and the constant b (See eq. below).

Homework Equations

We know that the maximum compression for two spheres colliding is given by
Em=((5/4b)uv^2)^5/2 where v is the initial velocity upon collision and u is the reduced mass u=m1m2/(m1+m2). b is a constant.

The Attempt at a Solution

Now my only question is what to use as the reduced mass. Mathematically by putting in infinity as m2 we get a reduced mass of 1. Is this correct?

 

[MathematicalPhysicist]

mathmetically it's: m1.
but physically you are given that m2>>m1.