# what is work? occurs when a force causes an object to move what is force? a push or a pull on an...

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• What is WORK?Occurs when a FORCE causes an object to moveWhat is FORCE?A PUSH or a PULL on an object

• What is a Simple Machine? A tool that helps make work easierA machine makes work easier by changing the size or direction (or both) of a force

The FORCE and OBJECT have to go the SAME directionWORKWORK

• Machines do NOT save work. They just make work EASIER

The SAME amount of work is still doneHave you ever used a ramp to load a heavy object into a pick-up truck?

• Types Of Simple MachinesAll machines are made from these 6 simple tools:1. Lever2. Inclined plane3. Wedge4. Screw5. Wheel and axle6. Pulley

• PulleysA simple machine consisting of a wheel that holds a rope changes the direction and/or amount of force needed to lift an object3 types of pulleys:1. Fixed Pulley 2. Movable Pulley3. Block and Tackle

• What is a Pulley?A pulley consists of a rope wrapped around a grooved wheel.The rope of chain is wrapped around the wheel, and one end is attached to the load.The other end is pulled to move the load.

• Why Use a PulleyA pulley can change either the size or the direction of a force.Pulley SystemsMore than one pulley can be used in a pulley system to reduce the force needed even more. The more pulleys in a system, the greater the distance you will have to pull the rope.

• A simple machine that is a straight, slanted surfaceThe longer the inclined plane is compared to its height, the easier it is to make to the tophttp://www.youtube.com/watch?v=pG_kT565-XQ

What is an INCLINED PLANE?

• An inclined plane is a simple machine with a flat slanted surface.

Inclined Plane

• Inclined planes reduce the force needed and to make work easier.The longer the plane the greater the distance and the less force needed.

Inclined Plane

• Some examples of an inclined plane are

• Simple Machines Reflection

PulleyInclined PlanesDefinitionDraw at least 3 real world examples of a pulleyWrite 1 sentence for each picture explaining how it makes work easierDefinitionDraw at least 3 real world examples of inclined planesWrite 1 sentence for each picture explaining how it makes work easier