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## Simple Machines

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**Simple Machines**Mr. King’s Science Classes**Introduction**• Simple machines are machines with few or no moving parts. • There are 7 main Simple Machines.**Kinds of Simple Machines**• We will be learning about the seven simple machines. They are: • 1. Lever • 2. Inclined Plane • 3. Wedge • 4. Screw • 5. Wheel and Axle • 6. Pulley • 7. Gears**Energy and Work**• Suppose you needed to move an object. You might use tools to help you. Simple machines are tools that use energy to do work. • Energy is the ability to do work. • You probably have used several of the seven kinds of simple machines.**1. What is a Lever?**• A hammer is a lever that helps do work. • Work is done whenever force makes an object move.**There are 3 different kinds or “classes” of levers.**• First Class Lever**First Class Lever**force**First Class Lever**force fulcrum**First Class Lever**force fulcrum weight**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: force fulcrum weight**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: force fulcrum weight Requires more force to move the weight but less distance**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: force fulcrum weight Requires more force to move the weight but less distance**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: force fulcrum weight Requires more force to move the weight but less distance**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: force fulcrum weight Requires more force to move the weight but less distance**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: force fulcrum weight Requires more force to move the weight but less distance**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: force fulcrum weight Requires more force to move the weight but less distance The weight moves a greater distance than the force.**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: force fulcrum weight Requires more force to move the weight but less distance The weight moves a greater distance than the force.**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight Now you have just the opposite, less force to move the weight but more distance.**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight Now you have just the opposite, less force to move the weight but more distance.**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight Now you have just the opposite, less force to move the weight but more distance.**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight Now you have just the opposite, less force to move the weight but more distance.**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight Now you have just the opposite, less force to move the weight but more distance.**First Class Lever**• By moving the fulcrum, the dynamics of the lever change. Here is how: • Now, move the fulcrum clear to the right and notice the difference. force fulcrum weight The weight does not move very much. Now you have just the opposite, less force to move the weight but more distance.**Can you guess what would be the dynamics if the fulcrum was**directly in the middle?**Can you guess what would be the dynamics if the fulcrum was**directly in the middle? Just a change in direction**Now for the 2nd class lever.**How would changing the position of the weight change the dynamics of this lever? force fulcrum weight**Now for the 3rd class lever.**How would changing the position of the force change the dynamics of this lever? force fulcrum weight**2. What is an Inclined Plane?**• A ramp is an inclined plane. • A ramp helps move objects. • You can use an inclined plane to help move an object to a higher or lower place.**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight**What is the mechanical advantage of the ramp or incline**plane? force What do you notice about the difference between these two ramps? weight What is the trade off between these two ramps?**3. What is a Wedge?**• A doorstop is a wedge. • A wedge is a simple machine used to push objects apart. • An ax is a wedge that splits wood. • A wedge could be considered a two sided incline plane.**4. What is a Screw?**• A screw is a simple machine used to hold objects together. • Think about your desk. • Does it have screws helping to hold it together? • A screw is an incline plane twisted on itself.**5. What is a Wheel and Axle?**• A wheel and axle is a simple machine made of a rod attached to the center of a wheel. • The axle, or rod, turns when you put force on the wheel. • You probably have seen a wheel and axle on scooters, cars, roller skates, and wagons.**6. What is a Pulley?**• A pulley is a simple machine with a wheel and with a rope. • The rope fits around the edge of the wheel. • You can use a pulley to move a load up, down or sideways.**How do Pulleys Work?**They can change direction of the load. force weight**How do Pulleys Work?**They can change direction of the load. force weight OR**How do Pulleys Work?**Using two different pulleys, with the weight attached to the bottom one with give you a mechanical advantage. force weight**How do Pulleys Work?**Using two different pulleys, with the weight attached to the bottom one with give you a mechanical advantage. force weight This is called a block and tackle. You will use less force to lift the weight but will have to pull more rope.