Printable Student Sheet
Lab Sheet: Exploring Forces
Introduction:
In this lab, you will explore forces by measuring gravitational force and by
estimating the amount of force needed to lift different objects. A force is a
push or a pull. As you have observed in Motion Force, forces cannot be
seen, but we can measure the size of their effects on objects or systems.
The unit of measure of force is the Newton.
Materials:
99 Spring (can be a coil spring or a piece from a spring toy)
99 Washers
99 Two metersticks
99 Force meter
99 Two or more heavy books
99 Flat work surface
99 100g hanging mass
99 500g hanging mass
Motion Force
Teacher Guide
Lab Sheet: Exploring Forces
Procedure:
A. Lay one of the metersticks on the work surface with about 1/4 meter
of the stick hanging off the edge of the work surface. Hold the
meterstick in place by setting the books on the stick.
B.
Place the spring on the meterstick so it hangs freely off the edge of
the work surface.
C. Use the other meterstick to measure the length of the spring, which
is the distance from the bottom to the top of the spring. Enter the data
in the second column of the chart.
D. Repeat step C using one washer attached to the spring. Keep repeating
until you have five washers attached to the spring.
E.
Calculate the stretch of the spring by finding the difference between
the original measured length and the length after adding each washer.
Enter this data in the third column of the data chart. Use 0 as the
stretch of the spring for 0 washers.
Number of Washers
Length of Spring (mm)
0
1
2
3
4
5
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Teacher Guide
Lab Sheet: Exploring Forces
Stretch of Spring (mm)
F.
Motion Force
Make a line graph of your results. Use Gravitational Force (Number
of Washers) as the x-axis and Amount of Stretch (mm) as the y-axis.
Teacher Guide
Lab Sheet: Exploring Forces
G. What is the relationship between the amount of stretch and the
number of washers?
H. In the experiment, the washers exerted a force on the spring. Now you
are going to use a force meter to measure forces. Hang the 100g mass
on the force meter. How much force is required to hold the mass?
I.
Repeat step H with the 500g mass. How much force is required to
hold the mass?
J.
Use the force meter and the washers from the experiment to find out
how many washers exert 1 N of force.
K.
Now that you are familiar with 1 Newton of force, estimate the force
needed to lift the following objects. Remember, it took 1 N to hold the
100g mass. You can hold the 100 g mass in your hand to get an idea
of what lifting 100 grams feels like.
99 basketball
99 notebook
99 stapler
99 hammer
Motion Force
Teacher Guide
Lab Sheet: Exploring Forces