Home Page | Curriculum
Home Page | USOE Home Page
Copyright © by the Utah State
Office of Education.
||Students will construct various machines
and compare the work done by them.
|Topic: Changes in
|Objective 3240- 0401
||Construct simple machines and use them
to measure and analyze work done by them.
||1a Make observations and measurements
2d Collect and record data using procedures
designed to minimize error.
5a Know science terminology appropriate
to grade level.
6d Construct tables, graphs, charts, diagrams
and models to describe and summarize data.
Description of Activity :
Title of Activity: Lever Action
Activity Overview: Students will be introduced to the
concept of levers. They will then be given time to discover
how levers work and what type of levers exist.
Duration of Activity: 50 minutes
Materials, Facilities and Resources:
a hammer, a nail, a 2 foot long 2x4 stud, 10 - 12 meter
sticks, 10 -12
heavy weights (bricks, texts, 1 kg. weights, etc.) 10 - 12
plastic mugs to serve as fulcrums (laying sideways on table).
The three parts of a lever, fulcrum, resistance arm and effort
arm, work together to make it possible to lift a weight using
less force. The placement of the fulcrum, resistance and effort on
the lever determine what type it is. There are 3 types of levers.
They are classified as 1st class, 2nd class, and 3rd class. They
can be diagramed as follows:
Which lever is used depends on the job that needs to be done. The
screwdriver is an example of a 1st class lever, a wheelbarrow is
a 2nd class lever and a broom is a 3rd class lever. In this activity a 1st
class lever should be easiest to use, especially if the resistance
arm is shorter than the effort arm.
Teaching and Learning Strategies:
Ensure Inquiry: Do Not discuss levers until after
the nail demonstration.
Do Not discuss the 3 types of levers until the students have
completed their experiments.
Prerequisite Instruction: none
Invitation to Learn:
1. Pound a nail into the 2" x 4" stud and have
students attempt to remove the nail without using the hammer.
2. After several students have attempted to remove the nail,
allow one student to use the hammer to remove the nail.
3. Ask the students, "Why was it easier to remove the
nail by using the hammer?" Follow this up by having the
students label (on their activity sheet ) the forces acting
on the hammer.
4. Tell the students that the hammer was acting as a lever.
5. Describe the key elements of a lever (fulcrum, effort,
resistance) and have the students indicate these in their
activity sheets by the drawing of the hammer.
6. Arrange the students in groups of 3 and pose the problem:
What arrangement of a fulcrum, a force and a resistance will
provide the greatest ease in lifting a weight if only your
"pinky" finger is used as the applied force?
7. Tell the students to try as many combinations as possible
(minimum of 7 ). Encourage students to use a variety of
placements and arrangements of the effort, resistance and
fulcrum. Tell the students to keep track of all lever
8. Allow for 25 minutes of investigation.
9. Following the investigation phase, go around the room and
have each group draw their most successful and their least
successful arrangements on the board. Make sure that the
fulcrum, effort and resistance are indicated on the
10. Introduce the 3 types of levers by using the students
drawings. Indicate which drawings are 1st class levers, 2nd
class levers and 3rd class levers and explain why they fit
these categories. If a type of lever is missing, draw this
one on the board and ask if any students tried this
11. Introduce the concept of work. (Work = force x distance)
12. Tell the students the weight of the object they were
lifting. See if they can generate the idea that they traded
force (weight of object) for distance (movement of the lever
Safe Operating Procedures: No unusual
Summary of Learning:
Assessment of Learning: Evaluate the student's activity
Multiple Choice Items:
1. How does using a lever make lifting an object easier?
a. it reduces the weight of the object
b. it reduces the work
c. it trades force for distance
d. it requires more energy but less work
e. it doesn't make it easier
2. What type of lever is illustrated by the following
a. a 1st class lever
b. a 2nd class lever
c. a 3rd class lever
d. a 4th class lever
e. a 5th class lever
Student Activity Sheet for "Lever Action"
1. Drawing of hammer:
(label fulcrum, resistance, effort)
2. Your data: label drawings
- amount of effort as high, medium or low.
1. Which type of lever made it easiest to lift the weight?
2. Diagram this lever:
3. What does a lever "trade" for force?
4. Name three commonly used levers.
All rights reserved except those which may be
granted under Sections 107 and 108 of the Copyright Revision Act
of 1976. This document may be freely distributed in its entirety
for non-profit purposes provided that the copyright notice is not
removed. If you have questions concerning proper use of this
material, or if you are interested in obtaining permission,
contact the Curriculum Section Reception Desk at 801-538-7698.
This document was submitted for posting to the Internet by the
State Science Specialist. Any questions concerning content should
be directed to that individual.
Updated September 18 1997 by Michelle Dumas