Question

A 400-g block with an initial speed of 80 cm/s slides along a horizontal tabletop against a friction force

of 0.70 N. (a) How far will it slide before stopping? (b) What is the coefficient of friction between the block

and the tabletop?

Answer 1

a)

$$0.5(0.4)(0.8)^2=0.7d\\d=0.18\ m$$

b)

$$\mu=\frac{0.7}{0.4\cdot9.8}=0.18$$