Wednesday, March 3 rd Agenda  Quick Review of section 8.2  Finish section 8.2  The Inclined Plane Family  In-Class Assignments:  Section 8.2 review, pg. 262, #1-4  Section 8.2 study guide  Quiz over section 8.2  “The Pyramids” Worksheet  Inclined Plane Quick Activity

Quick Review What is the definition of a simple machine? One of the six basic types of machines of which all other machines are composed.

Quick Review List the 6 Simple Machines 1.Simple lever 2.Pulley 3.Wheel and axle 4.Simple inclined plane 5.Wedge 6.Screw

Quick Review What are the 3 classes of levers and how are they different from each other? 1.1 st class levers Fulcrum in middle Input and output forces at opposite ends of arm 2.2 nd class levers Fulcrum at one end of arm Input force applied to opposite end of arm 3.3 rd class levers Fulcrum at one end of arm Input force applied in middle of arm

Quick Review How is a pulley like a lever? The point in the middle of a pulley is like the fulcrum of a lever and the rest of the pulley acts like the arm. What is it called when multiple pulleys are put together into a single unit? Block and tackle

Quick Review How are a wheel and axle like a lever? A wheel and axle is a lever or a pulley connected to a shaft.

The Inclined Plane Family  A loading ramp is another type of simple machine, an inclined plane.

Inclined Planes Multiply and Redirect Force  An inclined plane turns a small input force into a large output force by spreading the work out over a large distance.  Pushing something up a long ramp that rises gradually is easier than pushing something up a short, steep ramp.

A Wedge is a Modified Inclined Plane  A wedge works like 2 inclined planes back to back.  Using a wedge is like pushing a ramp instead of pushing an object up the ramp.  A wedge turns a single downward force into 2 forces directed out toward the sides.  Examples of wedges: nails, axe blade or log splitting wedge

A Screw is an Inclined Plane Wrapped Around a Cylinder  Like pushing an object up a ramp, tightening a screw with gently sloping threads requires a small force acting over a large distance.  Tightening a screw with steeper threads requires more force.  Examples of screws: Jar lids, spiral staircases, machine screws

Compound Machines  A machine made of more than one simple machine is called a compound machine.  Examples of compound machines are: Scissors, which use two first class levers joined at a common fulcrum A car jack, which uses a lever in combination with a large screw

In-Class Assignments  In-Class Assignments:  Section 8.2 review, pg. 262, #1-4  Section 8.2 study guide

Section 8.2 Quiz  You may use your book and/or your guided notes.

“The Pyramids” Worksheet  Read the paragraphs and answer the questions.  Question #1 you can answer from the reading.  Question #2 Hint: 2.2 X 10 4 N = 22,000 N To solve: Work = Force X Distance  Questions #3 Hint: 4.5 X 10 4 N = 45,000 N 9.0 X 10 5 J = 900,000 J To solve: Distance = Work Force

Inclined Plane Quick Activity  Just like we did last week with the levers, now we will use books, etc. to test various types of inclined planes, or ramps.  Get with your lab partner and complete the “Inclined Plane Quick Activity” side of your worksheet… L ooking Ahead: Thursday will be a lab day with 3 different activities.