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\includegraphics[max width=\textwidth, alt={}, center]{470e70de-66ba-4dcc-a205-0c92f29471b1-3_200_897_269_625}
A block of mass 3 kg is placed on a horizontal surface. A force of magnitude 20 N acts downwards on the block at an angle of \(30 ^ { \circ }\) to the horizontal (see diagram).
- Given that the surface is smooth, calculate the acceleration of the block.
- Given instead that the block is in limiting equilibrium, calculate the coefficient of friction between the block and the surface.