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Cynthia Clemons John Palmer
5051 N. Kenneth Ave.
Chicago IL 60630
Students will explain what work is, measure work done in moving an object, and
tell how energy is related to work in both machines and the human body.
meter stick, bathroom scale, paper, pencil, and a flight of stairs
Part-A: How Much Work Can Your Body Do?
1. Students will walk up a flight of stairs, counting the number of stairs in
2. Students should measure (in centimeters) the height of one stair and multiply
that number by the number of stairs in the flight. This will give them the
3. Students weigh themselves using an ordinary bathroom scale and calculate
their weight in N (Newtons). 1 lb equals 4.5 N. This will give them the
4. Finally, students will calculate how much work is done when they walk up a
flight of stairs. Work is measured in N-meters. The formula for
measuring work is, W = F x D.
-Student correctly uses the meter stick to measure the height of one stair.
-Student correctly weighs himself using an ordinary bathroom scale.
-Student correctly calculates his weight in newtons.
-Student correctly calculates the distance in meters.
-Student correctly calculates the amount of work done in walking up a flight of
Part-B: Can Simple Machines Help Us Do Work?
construction paper (13 cm x 13 cm), straight pin, ruler, unsharpened pencil
(with an eraser), 45 cm length of string, one-quart size milk carton, scissors,
paper clip, a heavy object
1. Students build a model windmill using the 13 cm x 13 cm piece of
construction paper, the straight pin, and the unsharpened pencil.
2. Students should cut the top off the milk carton. Then cut 2 deep U-shaped
groves in opposite sides of the milk carton. Put a heavy object into the
carton to weigh it down.
3. Tie a paper clip to one end of a piece of string. Tape the other end of the
string to the writing end of the pencil.
4. Set the windmill into the groves of the milk carton at the edge of a table so
that the paper clip on the string hangs freely.
5. Students predict what will happen when air is blown across the top of the
windmill so that the blades catch the moving air.
6. Students should (by mouth), lightly blow across the top of the windmill so
that the blades catch the moving air.
-Student is able to make a reasonable prediction concerning the performance of
the windmill blades.
-Students can reasonably describe what happened when air was blown on the blades
of the windmill.
-Student is able to conclude that moving air on the wheel and axle of the wind-
mill allows the windmill to act as a simple machine.
Part-C: Our Body the Machine:
Pictures of foods, glue, scissors, construction paper, play food to represent
the four food groups, chart of the four food groups, chart showing the
recommended daily nutritional requirements, and a chart that shows the nutrients
found in some common foods. The chart should also include examples of food
sources and the body's need for each nutrient.
1. Students will run in place, and perform a set of jumping jacks.
2. Ask students what allows them to be able to perform these simple exercises?
3. Tell students that the energy needed to perform these simple exercises, comes
from the varied foods they eat.
4. Students use a nutrition chart to examine some common foods, their
nutritional value, and how the food supplies the body with energy.
5. Students give examples of "junk foods" and "healthy foods."
6. Students identify the four food groups and classify play food into the four
7. Students describe a balanced diet.
8. Students create a balanced lunch using some common lunch items.
9. Students use pictures of food items to create a collage that represents a
balanced breakfast, lunch, and dinner.
-Student correctly classifies foods into the four food groups.
-Student creates a collage of food choices that reflect a balanced breakfast,
lunch, and dinner.
(See the activity sheet on the next page.)
Activity Sheet: Part-A
How Much Work Can Your Body Do?
Materials: meter stick, bathroom scale, pencil, paper, and a flight of stairs
A. Weigh yourself in lbs. Calculate your weight in Newtons (1 lb equals 4.5
B. Walk up a flight of stairs. How many stairs are in the flight?
C. Measure the height of one stair.
D. Calculate the distance (The bottom of the flight to the top).
E. Calculate how much work you do in walking up the flight of stairs.
1. My weight is _____ lbs
2. The force I will use is my weight in Newtons. The force is _____
WORK SPACE _____lbs x 4.5 Newtons = _____
3. The height of one stair is _____ cm
4. The number of stairs in the flight is _____
5. The distance I will walk is _____ meters
WORK SPACE height of one stair _____ x _____ the number of stairs in the
6. Walk up the entire flight of stairs
7. How much work did you do when you walked up the flight of stairs?
_____ Newtons x _____ meters (distance) = _____ Newton-m of work
8. I can infer that a person with a __________ weight will do less work than a
person with a __________ weight when walking up a flight of stairs