Question

The spool has a mass of 100 kg and a radius of gyration of kc 0.3 m (Figure 1) Part A If the coefficients of static and kinetic friction at A are ?,-0.2 and Ha-0.15, respectively, determine the angular acceleration of the spool if P 54 N Express your answer to three significant figures and include the appropriate units. View Available Hint(s) LA igure 1 of 1> rad 0.7163 Submit Previous Answers X Incorrect; Try Again; 10 attempts remaining 250 mm 400 mm Provide FeedbaCK Next >

Answer 1

take moment about G H_e times 3 = (5 times 4) + (2 times 8.5) Rightarrow H_e = * I_a = mk^2 = 100 times 0.3^2 = 9 kgm^2 Sigma F_x = m a_gx Rightarrow F_A = 100 a_gx Sigma F_y = 0 Rightarrow 54 + N_A - 981 = 0 N_A = 927 N Sigma M_alpha = I_G alpha Rightarrow (-54 times 0.25) + (F_A times 0.4) = 9 alpha 0.4 F_A - 9 alpha = 13.5 - 1 IF No - slip condition a_gx = 0.4 alpha F_A = 100 times 0.4 alpha = 40 alpha Now, 0.4(40 alpha) - 9 alpha = 13.5 alpha = 1.92857 rad/s^2 Rightarrow Comment iF wrong