Torque & Equilibrium Practice Problems
A female worker in the workplace has a safe limit to lift objects weighing 160 N (16 kg) at places of work. The worker can lift weights greater than 160 N using a trolley. You may consider a 1.5 m long trolley, weighing 100 N, and the center of gravity located at 0.6 m from the axle. Assume the load's center of mass is located 0.6 m from the axle. What is the source of the force that enables the worker to lift more weight using the trolley?
A male person has a safe limit to lift objects weighing 250N (25 kg) at the workplace. How much load can the person lift using a 1.5 m long trolley weighing 100 N? The center of mass of the trolley is located 0.6 m from the axle supporting the wheels. Take the center of gravity of the load to be located at 0.6 m from the axle.
A 400 N hatch is located at the upper end of a stairway. Determine the total upward force a person standing on the staircase must apply to initiate door opening and the net force applied on the hatch by the hinges. Take the upward force to be applied midway of the edge opposite to the hinges.
A 180 N hatch in the ceiling is free to rotate about hinges on one of its ends. What net upward force applied at the door's center is required to start opening the door? What net force is exerted on the door by the hinges?