PDN We use Simple Machines every day. Some in daily tasks and even some in sports that we play. Write a short paragraph describing a recent time you used a Simple Machine (Recall from the Machines packet you read from).

The Development of Simple Machines

Objectives Identify systems having mechanical operations and explain their function.(Explain how all the simple machines work) Be able to tell the difference between the 3 classes of levers. Be able to tell the difference between the different types of common gears.

Machines Can be as simple as a knife,

Machines a bottle opener,

Machines or a claw hammer.

Machines A Machine is a device that does some kind of work by changing or transmitting energy. We use a machine to give us a mechanical advantage to make work easier to accomplish.

A shaduf, also spelled Shadoof,  hand-operated device for lifting water, invented in ancient times and still used in India, Egypt, and some other countries to irrigate land. http://www.britannica.com/EBchecked/topic/537571/shaduf

Shadoof or Shaduf https://www.youtube.com/watch?v=i5X_jwnb-Ok

What is a Lever? Mocomi Kids https://www.youtube.com/watch?v=E8RA9Kw_IaE

Difference between 2nd and 3rd Levers 2nd = Effort is at the END EFFORT then LOAD/RESISTANCE then FULCRUM 3rd = Effort is BETWEEN LOAD/RESISTANCE then EFFORT then FULCRUM

Let’s take a short quiz Take out a sheet of paper and put your name on it. You may use your notes to a identify the following class of levers. For each question, write down whether picture represents a first, second or third class lever.

#1

#2

#3

#4

#5

#6

#7

#8

#9

#10

Wheel and Axel Mocomi Kids https://www.youtube.com/watch?v=ndT35aqDfAQ

Wheel and Axel The Wheel and Axel helps us move heavy loads with less effort and reduced friction, thus giving us a mechanical advantage.

Wheel and Axel The steam turbine concept was created or derived from the wheel and axel principle to give engineers a mechanical advantage.

Pulleys Mocomi Kids https://www.youtube.com/watch?v=LiarGb_LK10

Pulley definition A pulley is a wheel on an axle that is designed to support movement and change of direction of a cable or belt along its circumference. Pulleys are used in a variety of ways to lift loads, apply forces, and to transmit power.

Simple Pulley Systems

Incline Plane Mocomi Kids https://www.youtube.com/watch?v=Zj_iWiXUZX8

Incline Plane Definition An Incline Plane is a ramp that assists in moving heavy objects up and down heights. The longer the distance of an incline plane, the less effort is needed.

Wedge Mocomi Kids https://www.youtube.com/watch?v=LAAwZird80k

Wedge Definition Based on the Incline Plane, a wedge separates an object, lift a heavy load or keeps an object from moving. All in in an effort to gain a mechanical advantage.

Screw Mocomi Kids https://www.youtube.com/watch?v=4oPPQpF7bHY

Screws

Screw Definition A simple machine of the inclined plane type consisting of a spirally grooved solid cylinder and a correspondingly grooved hollow cylinder into which it fits.

Gears A rotating machine part having cut teeth, which mesh with another toothed part to transmit torque. Two or more gears working in tandem can produce a mechanical advantage. Basic and Compound Gears https://www.youtube.com/watch?v=D_i3PJIYtuY&list=PLJHoydNo-lbQNxDuZ6HeMS69NGIlHLbgX&index=1

In your Journal, please draw and label each of the main types of Gears In your Journal, please draw and label each of the main types of Gears. When finished, have Mr. Klingaman check your work for a journal stamp.

Compound Gear Train

Bevel Gears

Spur Gears

Helical Gears

Worm and Wheel

Rack and Pinion

Rear differential in a Volvo 740 Some gears can be hybrids What kind of gears do you see?

The study of liquids under pressure Hydraulics The study of liquids under pressure

Hydraulic Brake Video https://www.youtube.com/watch?v=OjA-cZni7C0

The study of pressure in gases Pneumatics The study of pressure in gases

Pneumatic Brakes https://www.youtube.com/watch?v=-R7J9BIjNEw