Simple �Machines

0. Lever: A bar that pivots �on a fulcrum.

There are 3 classes of levers.

1. 1st Class Lever: The Fulcrum is �between the Load and the Input Force.

Example: see-saw

2. 2nd Class Lever: The Load is �between Fulcrum and the Input Force.

Example: Wheelbarrow

3. 3rd Class Lever: The Input Force �is between the Load and the Fulcrum.

Example:�Hammer

4. Incline Plane: Straight �Slanted Surface.

Example: Slide

The gentler the slope, the greater�the mechanical advantage.

Example: A gentler landing�than falling straight down.

5. Wedge: A Double Incline Plane

Example: Axe

5. Wedge: A Double Incline Plane

Example: Ax

6. Screw: Incline plane �wrapped around a post.

1. Wheel and Axel: Two circular objects �of different size working together.�Example: Door Knob, Ferris Wheel.

2. Pulley: A grooved wheel �strung with a rope.

There are 3 kinds �of pulleys.

2A. Fixed Pulley: The wheel �is fixed between the input �force and the load.��Mechanical �Advantage is 1.

2B. Movable Pulley: The load is attached �to the wheel. The input force is �applied to both ends.��Mechanical �Advantage is 2.

2C. Block and Tackle: A Fixed Pulley and �a Movable Pulley used together.��Mechanical �Advantage is 4.

3. Compound Machines: Any �two or more simple machines �used together.

3A. Example 1: Can Opener.�Wedge: Cutting Wheel�2nd Class Lever: Handles�Wheel & Axle: Hand Crank

3B. Example 2: Scissors.�1st Class Lever: Handles�Wedge: Cutting Blades

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3C. Example 3: Bicycle�Wheel & Axle: Wheels�1st Class Lever: Pedals�Fixed Pulley: Rear Wheel Gear

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