Question

I need the answers for #3, 4, and 5

m A block with mass m1 = 9.4 kg is on an incline with an angle 8 = 33' with respect to the horizontal. For the first question there is no friction between the incline and the block. 1) When there is no friction, what is the magnitude of the acceleration of the block? 5.3929 m/s2 Submit 2) Now with friction, the acceleration is measured to be only a = 3.63 m/s2. What is the coefficient of kinetic friction between the incline and the block? 0.208 Submit 3) mm mi To keep the mass from accelerating, a spring is attached with spring constant k = 167 N/m. What is the coefficient of static friction if the spring must extend at least x = 16 cm from its unstretched length to keep the block from moving down the plane? Submit

Answer 1

3) M, = 9.4 kg 0-33 k=167n/m ,x=16cm. mg coso mg sino= kxt to mg sino-koc mgcoso Ms= 9.4*9.81 xsin33 -1670.16 9.4 x 9.81 x 605 53 Ms = 0.3037 T=kx = (167 Nlm) (0.16m) T= 26.72N 5.) (m+m') gsino = ls imgcoso + 0.97 m'g.coso (9.4 +m') 9.8xsin 33'= 0.3637 * 9.4X9.81x10933 +0.93xm'x9.81% cos33 m's 10.0833 kg