Collision and friction question

[el_diablo549]

Homework Statement

This is just a question relating to an assignment I am doing, if a steel block mass m1 traveling at velocity v1 and friction of 0.1 hits a concrete barrier traveling at 0 with mass m2 with friction 0.6. they have an inelastic collision and travel 0.1m together.

Homework Equations

frictional force = mg*coefficient of friction
g=gravity=9.81m/s

The Attempt at a Solution

for this period of travel, is the friction force acting on the both items = m1*g*0.1+m2*g*0.6
or is it
(m1+m2)g*0.6?

 

[paisiello2]

I would guess the former.