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Supposed body A slides on a surface. The will be a kinetic friction that acts on body A and opposite its relative motion.

However, is there a kinetic friction that acts on the surface too i.e. the direction is opposite to the kinetic friction that acts on body A?

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  • $\begingroup$ Newton's 3rd law says you can't push on something without its pushing back. Friction or not, it doesn't matter. $\endgroup$ – Mike Dunlavey Jan 28 '15 at 20:40
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Yes. Friction is not exempted from Newton's 3rd Law.

Here's an example to demonstrate this: a table top, with a piece of paper on top of that, with you hand on top of that. If you push down and across the paper with the right amount of force in each direction it is possible that you can get your hand and the paper moving, with your hand moving faster than the paper. In this example, friction from the paper on your hand has a 3rd law pair back on the paper, which causes the paper to move as well.

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Of course, Newton's laws are valid on all forces provided that an inertial frame is considered (can apply in non inertial frames too, but let's not discuss that now as it is irrelevant). So okay, if you want to apply 3rd law on friction, there will be an equal and opposite force on the surface too. The best way to see this is a two-block problem where you place a block on another one. Now, the floor on which the lower block is kept shouldn't be too rough, a moderately rough surface will do. Now provide the upper block a velocity relative to the lower one. You will see that both blocks will move seperately initially and gradually they will start moving together afterwards. You may also choose to calculate the time at which they start moving together, provided you know the coefficient of friction and other details as may be required, but since that's not exactly the question here, I'll leave it for now. Diagram Reference

Use this link if you want a diagram reference for the situation I have described. Try applying Newton's second law and kinematics' relations to find the time at which start moving together and other parameters. I hope this answers your question!

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