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## Homework Statement

[/B]Block 1 of mass 3.0 kg is sliding across a flooe with speed ##v_1=2.00 \frac m s## when it makes a head-on,one dimensional,elastic collision with initially stationary block 2 of mass 2.0 kg.The coefficient of kinetic friction between the blocks and the floor is ##μ_k=0,30##

Find the speeds of (a) block 1 and 2 just after the collision.Also find (c) their final separation after friction has stopped them and (d) the energy lost to thermal energy because of the friction.

## Homework Equations

Energy-Momnetum conservation Equations

## The Attempt at a Solution

##Δ\vec p =\vec p_f-\vec p_i=F_{external}Δt##

So If we assume Δt is too small we can say ##Δ\vec p=0## so from that

##m_1v_1=m_1v'_1+m_2v'_2##

##6kg\frac m s=3kg v'_1+2kgv'_2##

And we know there's friction so there must be energy lost.From the Energy conservation

##\frac 1 2m_2(v'_2)^2+\frac 1 2m_1(v'_1)^2-\frac 1 2m_1(v_1)^2=W_{friction}=F_fΔx##

I don't know how to calculate Δx here.Also there's friction between two blocks..Where I should add it in the energy conservation equation ? And How can I calculate it

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