Question

Problem 2. The excavator bucket and its contents have a total mass of 800 kg with center of mass at G. Neglect the mass of the other components. Your solution must include clearly-drawn free body diagrams. (a) Determine the magnitude of the force in hydraulic cylinder CD and statee if it is in tension or compression. (b) Determine the magnitude of the force in hydraulic cylinder AB and state if it is in tension or compression. (c) Determine the magnitude and direction of the force acting at pin E. 0.25 m 0.25 m 0.3 m 0.1 m 0.2 m 1.25 m 0.6 m 0.4 m 0.3 m

Answer 1

F_BD of boom Now F_AB will have 2 components x & y as shown in fig therefore tan theta = 0.25/1.5 theta = 9.46 degree w = mg (weight) w = 800 times 9.81 = 7848 (N) therefore moment at E G sigma M_E = 0 (F_AB times cos 9.46 times 0.5) + (F_AB times sin 9.46 times 0.3) - (w times 0.1) = 0 implies (F_AB times 0.4932) + (F_AB times 0.0493) = 7848 times 0.1 implies F_AB = 1446.63 (N) therefore Force is hydraulic cylinder AB is 1446.63 (N) tension sigma F_x - E_x + F_AB cos (9./46) = 0 E_x = 1446.63 times cos (9.46) E_x = 1426.95 (N) & sigma F_y = 0 E_y - w - F_AB sin 9.46 = 0 E_y = 7848 + 1446.63 times (sin 9.46) E_y = 8085.76 (N) E = squareroot E_x^2 + E_y^2 E = squareroot (1462.95)^2 + (8085.76)^2 E = 8217.04 (N)