Free Body Diagram and Frictional Force
Draw FBD for the following three cases, respectively.
(a) Find the normal force $F_{N1}$ for the case 1, express your answer in terms of F, M, g, and a
trigonometric function of angle $\theta$;
(b) Find the normal force $F_{N2}$ for the case 2; express your answer in terms of F, M, g, and a
trigonometric function of angle $\theta$;
(c) Find the normal force $F_{N3}$ for the case 3; express your answer in terms of F, M, g, and a
trigonometric function of angle $\theta$;
(d) If the coefficient of kinetic friction $\mu_k$ between the block and the surface is 0.300 in all
three cases, and M = 10.0 kg, F = 12.0 N, $\theta$ = 30.0°, find the kinetic frictional force $f_k$ in
these three cases. Recall that the magnitude of gravitational acceleration g = 9.80 m/s².