Friction/heat kinetic energy - reactive force

[Dale]

All good points how would you approach the problem?

I like the approach by @haruspex

 

[TonyCross]

I like the approach by @haruspex

So do I...

 

[Dale]

So do I...

OK, so just use that and don’t change it.

 

[TonyCross]

OK, so just use that and don’t change it.

Thanks Dale, you actually answered my initial question earlier in the thread, haruspex made a really good examination of the physics. I think we can now call this question well and truly answered. Thanks to everyone who gave their input to the discussion.