ABSTRACT
This chapter begins by defining load, effort, mechanical advantage, velocity ratio and efficiency, where efficiency is then defined in terms of mechanical advantage and velocity ratio. A machine is a device that can change the magnitude or line of action, or both magnitude and line of action of a force. A simple machine usually amplifies an input force, called the effort, to give a larger output force, called the load. Some typical examples of simple machines include pulley systems, screw-jacks, gear trains and levers. The chapter discusses fundamental to the study of the behaviour of machines. A simple gear train is used to transmit rotary motion and can change both the magnitude and the line of action of a force, hence it is a simple machine. The chapter aims to understand and perform calculations with pulley systems understand and perform calculations with a simple screw-jack.
