Chapter 4.1, Problem 13R

To determine

To explain: the effects on the output work of a machine on lubricating it and also, the effects on the input and output forces.

Explanation of Solution

Introduction: The efficiency of a machine is the ratio of the output work to input work.

The ratio of the output work to the input work is known as the efficiency of a machine.

Machines can be made more efficient by reducing friction, which is done by lubricating the machine with oil or grease.

Thus, on lubricating a machine, its efficiency increases, that is, the output work increases.

Subsequently, as lubrication decreases friction, the output force also increases. However, input force remains unaffected as it depends on the person applying it.

Conclusion: Lubricating a machine, increases the output work of the machine.

Subsequently, on lubrication, the output force from the machine also increases. However, input force remains unaffected.