Welcome back minions.
Instructions and warm-up on the board.
QUIZ!!!
• Clear your desk.• Get out a sheet of paper.• Put your First and Last name on the top, along
with the period.• Number your paper 1 to 10.• Pay attention!!!
#1
This machine is a flat, sloped surface. It is usually used to lift an object.
#2
This machine is thick on one end and tapers to a smaller edge at the other end. This is usually
used for separating.
#3
This machine is an inclined plane wrapped around a cylinder.
#4
This machine is a rigid bar that is free to pivot or rotate at a fixed point.
#5
Which class lever is this?
#6
Which class lever is this?
#7
Which class lever is this?
#8 and #9
WORK = _________ x __________
#10
True or False
A Screwdriver can be used as a first class lever, a third class lever, a wedge, and a wheel and
axle.
Wheel and Axle
Where have you seen a wheel and axle before?
What is a wheel and axle?
Wheel and Axle:A machine made of two circular cylindrical objects fastened together that rotate about a common axis.
Good question yesterday…
What would the tool, the screwdriver, be classified as in reference to a simple machine?
Answer: Wheel and Axle
Mechanical advantage…
• The greater the ratio between the wheel and axle, the greater the mechanical advantage.
• Think of the wheels of the balloon racer!
Pulley
Where have you seen a pulley before?
What is a pulley?
Pulley:A simple machine made of a grooved wheel with a rope or cable wrapped around it.
How it works…
• You pull on one end of the rope.
• The other end is attached to the load.
• It changes the input force in two ways– Decrease input force– Change direction of
force.
Types of pulleys
• 3 Types of Pulleys:
Mechanical advantage
• Pulley’s mechanical advantage is equal to the number of sections that support the load.
Simple machines in the body…
• Some of you wondered about this…
Compound machines…
• Compound machine:– A machine that utilizes two or more simple
machines.
Homework
• Give me 3 examples of a compound machine.– Must have a picture of the compound machine.– Point out and identify the parts that are simple
machines.