4 A block \(B\) of weight 28 N is pulled at constant speed across a rough horizontal surface by a force of magnitude 14 N inclined at \(30 ^ { \circ }\) above the horizontal.
- Show that the coefficient of friction between the block and the surface is 0.577 , correct to 3 significant figures.
The 14 N force is suddenly removed, and the block decelerates, coming to rest after travelling a further 3.2 m .
- Calculate the speed of the block at the instant the 14 N force was removed.