Mechanical advantage and velocity ratio: levers, inclined planes, screws and pulleys

What this note covers

1. Mechanical advantage compares forces; velocity ratio compares motion
2. Levers use perpendicular moment arms
3. An inclined plane trades distance for lifting effort
4. A screw uses one turn of travel to create a small advance
5. Count the strands supporting the moving pulley block
6. Choose a mechanism using both force and movement requirements
7. Worked machine chain: lever driving a screw jack
8. Worked pulley diagnosis: support strands are not free rope ends

8 sections · 10 key terms & formulas · 6 common mistakes