Question

Review problem. A block having mass m and charge +Q is connected to a spring having constant k. The block lies on a frictionless horizontal track, and the system is immersed in a uniform electric field of magnitude E, directed as shown in the figure below. The block is released from rest when the spring is unstretched (at x0) (a) By what maximum amount does the spring expand? (Use the following as necessary: Q, E, and k.) (b) What is the equilibrium position of the block? (Use the following as necessary: Q, E, and k.) (c) Show that the block's motion is simple harmonic and determine its period. (Use the following as necessary: Q, e, m, and k.) (d) Repeat part (a) if the coefficient of kinetic friction between block and surface is Hk. (Use the following as necessary: k, m, E, Q, g, and k.)

Answer 1

(a) Force on charge will change into restoring force. Restoring force = -ke - Kx = QE a = QE K - ve indicates Restoring force is opposite to a E. (6) Equilibrium position at (B ) 2k OA K x ( from as) A = 2 time period : T = 2 1 2 LA = 3 = T = 20 (d) Restoring force QE - Mkong distance covered = x Kx'= QE - peking K= QE - Hema tieng x=GE - Ming