Work, Energy, and the Simple Machine: Lever, Wheel and Axle, Pulley – United Streaming

  1. The turning point of a lever is called the ______.
  2. The load or object being moved on a lever is called the ______.
  3. The mechanical advantage of a wheel and axle is determined by:_____

a)dividing the diameter of the wheel by the diameter of the axle.

b)dividing the axle radius by the wheel radius

c)measuring the length of the effort arm

d)dividing the resistance arm by the effort arm

  1. How do we calculate the mechanical advantage of a movable pulley? _____

a) Divide the length of the effort arm by the length of the resistance arm.

b) Divide the wheel radius by the axle radius.

c)Measure the length of the effort arm.

d) Count the number of support strands of rope.

  1. How do we calculate the mechanical advantage of a lever? ______

a)Divide the length of the effort arm by the length of the resistance arm.

b)Divide the wheel radius by the axle radius

c)Divide the length of the resistance arm by the length of the effort arm

d)Divide the weight of the load by the effort arm.

  1. What is energy?
  1. Name the six simple machine?
  1. How is a fixed pulley different from a movable pulley?
  1. What is a block and tackle?
  1. There are three kinds of levers what makes them different from each other?

Name:______Date:______Period:____

Brain Pop:

What are the four parts of a lever:

What is a Class I lever:

What is a Class II lever:

What is a Class III lever:

Lever Quiz

1)What is a lever?

2)What might you use a lever for?

3)What is the pivot point of a lever called?

4)What do you call the force that you apply to the lever?

5)What do you call the weight or resistance that needs to be overcome?

6)What defines a class one lever?

7)What defines a class two lever?

8)What defines a class three lever?

9)What kind of lever is you arm?

10) How is a class three lever different from class one and class two levers?

Name:______Date:______Period:____

Levers are one of the basic tools that were probably used in prehistoric times. Levers were first described about 260 BC by the ancient Greek mathematician Archimedes (287-212 BC). A lever is a simple machine that makes work easier for use; it involves moving a load around a pivot using a force. Many of our basic tools use levers, including scissors (two class 1 levers working together), pliers (2 class 1 levers), hammer claws (a single class 1 lever), nut crackers (two class 2 levers), and tongs (2 class 3 levers).

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Item / Number of Class 1 Levers Used
see-saw / / a single class 1 lever
hammer's claws / / a single class 1 lever
scissors / / 2 class 1 levers
pliers / / 2 class 1 levers

In a Type 1 Lever, the pivot (fulcrum) is between the effort (input force) and the load (output force). In an off-center type one lever (like a pliers), the load is larger than the effort, but is moved through a smaller distance. Examples of common tools (and other items) that use a type 1 lever include:

In a Type 2 Lever, the load is between the pivot (fulcrum) and the effort.

Item / Number of Class 2 Levers Used
stapler / / a single class 2 lever
bottle opener / a single class 2 lever
wheelbarrow / / a single class 2 lever
nail clippers / Two class 2 levers
nut cracker / Two class 2 levers

Examples of common tools that use a type 2 lever include:

In a Type 3 Lever, the effort is between the pivot (fulcrum) and the load.

Item / Number of Class 3 Levers Used
fishing rod / / a single class 3 lever
tweezers / Two class 3 levers
tongs / / Two class 3 levers

Examples of common tools that use a type 3 lever include: