The ancient Egyptians built dozens of large stone pyramids as tombs for the bodies of kings and queens. The largest pyramid is made of more than 2 million blocks with an average weight of 2.5 tons and the largest blocks weigh 15 tons. How do you think the Egyptians got these huge stones onto the pyramids? DO NOW

One theory is that the Egyptians used ramps (inclined planes) coated with mud to reduce friction. If the ramps had a mechanical advantage of 3, the average block would take 14 people to pull one average stone up the ramp. DO NOW

Many Theories, Still Unsolved

SIMPLE MACHINES Essential Question: What are the six types of simple machines and how do they work? Objective: SWBAT cite textual evidence IOT distinguish between the six types of simple machines and understand how they work. Agenda for Monday, March 23, 2015 – Do Now/Collect Any Missing Work – Cornell Notes: Simple Machines – Simple Machines Booklet HW: Finish Simple Machines Booklet

What is a Simple Machine? A Simple Machine is a tool that helps people do work by making a job easier to do. They have few to no moving parts. Some reduce the amount of force you have to use while others change the direction of the force you use.

LEVERS A rigid arm that is free to turn about a fixed point called the fulcrum – a pivot point Force is transferred from one part of the arm to the other 3 parts : – 1. Resistance, Output Force or Load (what you’re lifting) – 2. Effort or Input Force (the effort you put in) – 3. Fulcrum – the pivoting point

LEVERS

3 Classes of Levers 1 st Class: Fulcrum between Load and Effort – Examples: Seesaw, crow bar, scissors (compound)

3 Classes of Levers 2 nd Class: Load between effort and fulcrum – Examples: Wheelbarrow, Bottle Opener, Nutcracker (compound)

3 Classes of Levers 3 rd Class: Effort between load and fulcrum – Examples: Your forearm, hammer, fishing rod

PULLEYS Pulleys are like modified levers. The point in the middle is like the fulcrum while the rest acts as the arm. Used to lift heavy objects – Examples: Crane system – flag pole system

PULLEYS Single pulleys have a mechanical advantage of 1.

PULLEYS Moving pulleys or systems of pulleys can increase the mechanical advantage.

WHEEL AND AXEL A Wheel and Axel is a lever or pulley (wheel) connected to a shaft (axel). When wheel is turned, axel also turns and the force is multiplied. – Examples: Screwdriver, Steering Wheel

INCLINED PLANE An inclined plane is a flat surface that is higher on one end Allows us to raise an object with less effort than if we lifted it directly upward. – Examples: handicap ramp, moving truck, pyramids

WEDGE A wedge is two inclined planes together used to raise an object or split an object – Examples: Knife, door wedge, ax

SCREW A screw is an inclined plane wrapped around a pole or shaft that is used to hold materials together or drill holes.

Compound Machines Compound machines are made of two or more simple machines working together.

Checking for Understanding Number 1 is an example of a ____________________

Checking for Understanding Number 1 is an example of a PULLEY

Checking for Understanding Number 2 is an example of a ____________________

Checking for Understanding Number 2 is an example of a LEVER

Checking for Understanding Number 3 is an example of an _________________

Checking for Understanding Number 3 is an example of an INCLINED PLANE

Checking for Understanding Number 4 is an example of a ____________________

Checking for Understanding Number 4 is an example of a SCREW

Checking for Understanding Number 5 is an example of a ____________________

Checking for Understanding Number 5 is an example of a WHEEL AND AXEL

Checking for Understanding Number 6 is an example of a ____________________

Checking for Understanding Number 6 is an example of a WEDGE

CONCLUDING ACTIVITY Create an “acrostic” to use as a memory tool for the 6 simple machines: Examples: Louis Plank Was an Interesting, Witty Scholar (Lever, Pulley, Wheel and Axel, Inclined Plane, Wedge, Screw) Please Excuse My Dear Aunt Sally (Parentheses, Exponent, Multiplication/Division, Addition/Subtraction)

Simple Machines Booklet – Directions pgs Cover – Title (“Simple Machines”), Full name, Period, Date; Bonus Points for Drawing a Simple Machine Page 1 – Title: “Lever”; Finish the sentence – “All levers have a rigid ______________ that turns around a point called the ___________________. “ Draw the three classes of levers (Figure 5A, 5B, 5C), and give real-world examples of each. Page 2 – Title: “Pulley”; How is a pulley like a lever? Draw and label a fixed pulley (6A). What is the mechanical advantage of a fixed pulley? Draw and label a moving pulley (6B). What is the mechanical advantage of a moving pulley? Draw and label a block and tackle (6C). What is the mechanical advantage of a block and tackle? Page 3 – Title: “Wheel and Axle”; Finish the sentence – “A wheel and axle is made of a __________________ connected to a ________________.” Give 3 real-world examples of wheel and axles. Draw figure 7. Page 4 – Title: “Inclined Plane”; Draw and Label an Inclined Plane (Figure 8A). What is the output force equal to? Finish the sentence: “An inclined plane turns a small input force into a large output force by_______________.” Page 5 – Title: “Wedge”; A wedge is in the ________simple machine family. How does a wedge work? (Hint: Figure 8 B). Draw and label a wedge. Give a real-world example of a wedge. Page 6 – Title: “Screw”; What is the definition of a screw? (Hint: Figure 8C). Draw and label the parts of a screw. Give 3 real-world examples of a screw. Back Cover – Title: “Compound Machines”; What is the definition of a compound machine? Draw a pair of scissors and label the different simple machines that make it up. How many simple machines can you identify that make up a bicycle?