Exam 12: Mechanical Power Transmission

In a simple machine which has a velocity ratio of 8 and the law giving the relationship between the effort E and load F is E = 0.2F + 0.25 N, the effort required to overcome friction is:

Decide whether each of these statements is True (T) or False A belt drive is installed with an initial tension of 400 N in the belt. For a maximum permissible tight side tension of 500 N and the belt moving with a speed of 3 m/s: (i) The slack side tension will be 100 N. (ii) The maximum power that can be transmitted is 1200 J.

A screw jack has a screw with a pitch of 12 mm and a jack handle with a radius of rotation of 0.4 m. If the load to be lifted by the jack is 10 kN, the effort that must be applied to the jack handle is:

Decide whether each of these statements is True (T) or False A 100% efficient gear system has a gear ratio of 3 to 1. When a torque of 200 N is applied and the input Shaft rotates at 20 rev/s: (i) The output shaft rotates at 30 rev/s. (ii) The output shaft torque is 600 N m.

In a simple machine which has a velocity ratio of 8 and the law giving the relationship between the effort E and load F is E = 0.2F + 0.25 N, the limiting efficiency is: