Laws Of Motion

A block of mass $m=2 \mathrm{~kg}$ is initially at rest on a horizontal surface. A horizontal force $\mathbf{F}_1=(6 \mathrm{~N}) \hat{\mathbf{i}}$ and a vertical force $\mathbf{F}_2=(10 \mathrm{~N}) \hat{\mathbf{j}}$ are then applied to the block. The coefficients of static friction and kinetic friction for the block and the surfaces are 0.4 and 0.25 , respectively. The magnitude of the frictional force acting on the block is (assume, $g=10 \mathrm{~m} / \mathrm{s}^2$ )