1. KP1: What is a machine? A machine is something that makes tasks easier for humans Normally, it does this be reducing the force needed to move things

2. KP2: What are some examples of machines? Machines can be simple or complicated – Some simple types of machines are: Lever: a bar resting on a pivot or fulcrum Inclined plane: a flat surface tilted at an angle pulley: a wheel with a rope attached.

3. Let’s classify!

4. How do machines make tasks easier for us? Machines do not reduce the amount of work we have to do, but they can reduce the amount of force we need

5. KP4: What is force? Work = force x distance

6. Example If an elephant needs to be lifted up 4 feet, and it will require 5000 N of force… Force: ____________ Distance: ____________ Work: ____________

7. BUT let’s say we use an inclined plane to do this (ie: we push an elephant up a ramp instead of just lifting it). Let’s draw what this would look like: Does the machine make the distance bigger or smaller: ______ Does the machine make the force bigger or smaller: ________

8. Guided Practice A)A force of 100 N is applied in lifting a concrete block 1.5 meters. How much work is done lifting the block? A)B) An inclined plane is used to lift the same block, but it is now dragged up a ramp that measures 5 meters on the diagonal. How much force is required?

9. A) A construction worker needs to lift a piano up to the 3 rd story of a building. If he were to lift the piano straight up, he would need 50 000 N of force to lift it 8 meters. How much work would he need to do? B) Instead, he uses a pulley system and pulls down on the rope 20 m. If he is doing the same amount of work to lift the piano, how much force is needed?