Laws Of Motion

A block of mass $\sqrt{2} \mathrm{~kg}$ is placed on a rough horizontal surface. A force ' $F$ ' acting upwards at an angle of $45^{\circ}$ with the horizontal causes the block to start motion. If the coefficient of static friction between the surface and the block is 0.25 , the magnitude of the force ' $F$ ' is

(Acceleration due to gravity $=10 \mathrm{~ms}^{-2}$ )