Efficiency of simple machines - JSS2 Basic science Lesson Note

The efficiency of a simple machine refers to how well it performs its intended task with minimal waste of energy. Simple machines are designed to make work easier by either increasing the force applied, changing the direction of the force, or multiplying the distance the force is applied over. However, no machine is 100% efficient, as some energy is always lost due to factors like friction, heat, and air resistance.

Efficiency is often expressed as a ratio of output work to input work, multiplied by 100 to get a percentage. For example, if a machine requires 100 joules of input work to perform a task and only delivers 80 joules of output work, its efficiency would be 80%.

Increasing efficiency involves reducing energy losses through factors like lubrication to reduce friction, proper alignment of components, and using materials with low resistance. However, it is essential to balance efficiency improvements with factors like cost and complexity.