Work and Machines

What is Work?

Work is done when a force is used to move an object over a distance in the direction of the force. The formula for work is:

Work (W) = Force (F) x Distance (d) x cos(θ)

Types of Simple Machines

• Lever: A rigid bar that pivots around a fixed point (fulcrum).
• Pulley: A wheel with a groove that a rope or belt can fit into, used to change the direction of a force.
• Wheel and Axle: Consists of a large wheel attached to a smaller shaft, used to transmit force.
• Inclined Plane: A flat surface with one end higher than the other, used to reduce the force needed to lift an object.
• Wedge: A thick end and a thin end, used to split or separate objects.
• Screw: An inclined plane wrapped around a cylinder, used to hold objects together or lift loads.

Mechanical Advantage

Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device, or machine system. It is calculated using the formula:

Mechanical Advantage (MA) = Output Force / Input Force

Study Tips

1. Understand the concept of work and how it is calculated using the work formula.
2. Memorize the different types of simple machines and their functions.
3. Practice calculating mechanical advantage for different machines.
4. Use diagrams and real-life examples to understand the application of simple machines.
5. Review and understand the relationship between force, distance, and work done.