What is mechanical advantage? 5/8/2018 What is mechanical advantage?

Mechanical advantage is the amount of help that a machine gives you. 5/8/2018 Mechanical advantage is the amount of help that a machine gives you.

5/8/2018 What is WORK?

Work occurs when a force moves an object over a distance. 5/8/2018 Work occurs when a force moves an object over a distance.

5/8/2018 What is a FORCE?

A force is a PUSH or a PULL. 5/8/2018 A force is a PUSH or a PULL.

5/8/2018 What is a PULLEY?

A pulley is a simple machine. 5/8/2018 A pulley is a simple machine. It is made with a grooved wheel and a rope.

5/8/2018 What is a GEAR?

5/8/2018 A gear is a simple machine. It is a toothed wheel that meshes another toothed mechanism. It can change the speed, direction, or amount of force needed to do work.

When the teeth of two gears are in contact with each other they are… 5/8/2018 When the teeth of two gears are in contact with each other they are…

5/8/2018 Meshed

5/8/2018 What are the names given to the first, middle and last gears in this Gear Train? ? ? ?

5/8/2018 Idler

If the follower gear is moving faster, it is called… 5/8/2018 If the follower gear is moving faster, it is called…

5/8/2018 Gearing Up

What direction is the follower gear moving in? 5/8/2018 What direction is the follower gear moving in? Driver Follower ?

Identify the following: 5/8/2018 Identify the following: Gear Teeth Axle Meshed Area

This is an example of what type of pulley system? 5/8/2018 This is an example of what type of pulley system?

A Movable Pulley System 5/8/2018 A Movable Pulley System A movable  pulley  is a pulley that moves with the load. The advantage of a movable pulley is that the effort needed to move the load is less than the weight of the load. The disadvantage is that the load is moving in the same direction as the effort and this is not always convenient.

This is an example of what type of pulley system? 5/8/2018 This is an example of what type of pulley system?

The fixed pulley is attached to an unmovable object. 5/8/2018 A Fixed Pulley System The fixed pulley is attached to an unmovable object.  The advantage is that the direction of the effort needed to move the load is opposite to the load itself. The disadvantage is that you have to apply the same effort to lift the load as the weight of the load.

This is an example of what type of pulley system? 5/8/2018 This is an example of what type of pulley system?

A Block and Tackle Pulley System 5/8/2018 A Block and Tackle Pulley System The Block and Tackle pulley system is made up of two or more pulleys.  The advantage is that the direction of the effort needed to move the load is opposite to the load itself. Another advantage is that the effort needed to move the load is less than the weight of the load.

What type of pulley system does NOT give you mechanical advantage? 5/8/2018 What type of pulley system does NOT give you mechanical advantage?

5/8/2018 A Fixed Pulley System

5/8/2018 What is the effort needed to lift a load of 120N using this pulley system?

5/8/2018 30 Newtons

Block and Tackle Pulley 5/8/2018 Match the following: 1 Fixed Pulley A Movable Pulley B 2 Block and Tackle Pulley C 3

Match the following: Spur Gear Worm Gear Bevel Gear A 1 B 2 C 3 5/8/2018 Match the following: A Spur Gear 1 B Worm Gear 2 Bevel Gear C 3

5/8/2018 What is different about the way gears on a bicycle turn in comparison to standard spur gears?

The gears turn in the same direction. 5/8/2018 The gears turn in the same direction. Bicycles have sprocket and chain gears that work like some pulley systems. A chain connects the sprocket gears on the pedals to the back wheel. The chain also allows the gears to turn in the same direction. The sprockets keep the chain from slipping as it turns.

5/8/2018 Why might a Block and Tackle pulley system be the best choice in this situation?

5/8/2018 A Block and Tackle pulley is a good choice in this situation because the amount of effort needed is less which is good for heavy loads. Also, the direction of the effort is opposite with a Block and Tackle pulley. It is easier to “pull down” in order to lift because you can have gravity help you.

Why was a movable pulley not a good choice in this example? 5/8/2018 Why was a movable pulley not a good choice in this example?

5/8/2018 With a movable pulley the effort is in the same direction as the load. If the load is moving up, the person would need to pull up which would be awkward.

This is an example of gearing up. 5/8/2018 How many times would the follower gear rotate if the driver gear were to rotate 2 times? This is an example of gearing up. FOLLOWER DRIVER

This is an example of gearing up. 5/8/2018 How many times would the driven gear rotate if the driver gear were to rotate 3 times? This is an example of gearing up. DRIVER FOLLOWER

5/8/2018 What is the effort needed to lift a load of 50N using this pulley system?

5/8/2018 25 Newtons

5/8/2018 What is the effort needed to lift a load of 400N using this pulley system?

5/8/2018 200 Newtons

5/8/2018 Fill in the blanks: A gear train can change the _______, _______, or amount of _______needed to do work. A pulley system can change the _______ of effort and the _______ of effort needed to move a load.