The Inclined Plane!!
Name ____________________
Partner ___________________
Introduction. Two main concepts: Force and Mechanical Advantage.
1. Force. A force is any push or pull on an object. People, a machine, an animal or the Earth’s gravity are examples of things that
can supply a force.
a. The weight of an object is caused by the force of gravity. This force is measured in Newtons.
3. Mechanical Advantage occurs when a machine reduces force by increasing distance.
4. Machines are devices that people make to help move objects with less effort.
The inclined plane shown below makes work easier to do by going the longer distance up the slope.
That is, it is easier to walk up the slope then to climb the cliff!
In this investigation we will be varying the angle (slope) of an inclined plane.
For each angle studied, we will collect four pieces of information:
Effort Force: this is the force you need to drag the object up the incline.
Load Force: this is the weight of the object in Newtons as it hangs from a gauge.
Effort Distance: this is the distance you move up the inclined plane.
Load Distance: this is the height of the inclined plane.
Using this data we will determine the mechanical advantage of the inclined plane in two different ways:
Ideal Mechanical Advantage is a ratio of distances = effort distance / load distance
Actual Mechanical Advantage is a ratio of forces = load force / effort force
Which of these two Mechanical advantage measures is affected by friction? ____________________________________________
Question. How will the ideal and actual mechanical advantage be affected by increasing the angle of the
incline plane?
Hypotheses. Write a complete sentence hypothesis in the space below!
Procedure.
1. Measure the load force for a block of wood by hanging it freely from a blue spring force gauge and
determining its weight. This is the load force for every trial.
2. Set the inclined plane to 10 degrees
3. Measure the effort force for this angle by pulling the block up the inclined plane at a constant rate while
reading the force spring gauge.
4. Measure effort distance by measuring the total distance along the slope of the incline. This is a constant
effort distance for every trial.
5. Measure the load distance for this angle by measuring the vertical distance of the inclined plane.
Effort
distance
Load distance
6. Calculate each of the mechanical advantage ratios and place them in your data table for that angle.
7. Repeat the same procedure for angles of 20 degrees, 30 degrees and 40 degrees. You need only determine
the new effort force and load distance, the other values do not change for new angles.
8. By making several observations of the effort force at each angle you need only write down one.
9. Contribute your results to the class data table.
Group data table.
Angle
Load Force (N)
Effort Force
(N)
Load Distance
(cm)
Effort Distance
(cm)
100
2.25 N
0.75 N
8 cm
42.5 cm
200
2.25 N
1.20 N
15 N
42.5 cm
300
2.25 N
1.5 N
21.5 N
42.5 cm
400
2.25 N
1.75 N
27.5 N
42.5 cm
Class data table.
AMA
I.M.A.
10 degrees
20 degrees
30 degrees
40 degrees
Group
AMA
IMA
AMA
IMA
AMA
IMA
AMA
IMA
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Averages
3.08
4.56
1.88
2.33
1.50
2.09
1.32
1.43
Analysis.
1. What happened to the IMA and the AMA as the inclined plane angle increased?
2. Which of the two (IMA or AMA) was always larger? Why do you think this happened?
3. Efficiency = actual mechanical advantage / ideal mechanical advantage. Calculate the Efficiency of the class average inclined
plane at 100 and 400. At which angle was the inclined plane more efficient?
Conclusion. Include the following in your excellent conclusion!!
Questions
hypotheses
results, major findings
next logical experiment