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Jan_EE
A coffee cup of mass 230 g sits on a flat, horizontal table top. You push the cup across the table top with a constant speed of 3.2 cm/s. To do this, you must exert a horizontal force of magnitude 0.45 N. What is the magnitude of the frictional force acting on the cup as you push it?
This time it's constant speed, so that means a=0, so \(\Sigma F=0\). Do you need further help?
So the frictinal force is equal ro 0.45 right?