OBJECT:

To compare the mechanical advantage of an inclined plane, when the angle is varied.

MATERIALS:

* CAUTION *

This experiment has the potential of eye injury !! Be sure to wear your Safety Goggles at all times.

1. Set of weights, Rubber band scale set to zero.

2. Construct the set up in Fig one.

3. Attach your Rubber band scale to the to the roller cart:

4. Take the weight of your roller cart and record the weight. _____________ g

5. With the board ( the inclined plane, at an angle of zero degrees ) board resting on the table, pull on the Rubber band scale to find out how much effort it will take to keep the roller cart moving.

6. Record in the table below the RESISTANCE, EFFORT ANGLE OF INCLINE PLANE, and Calculate the MECHANICAL ADVANTAGE for each angle.

7. Also, for every given angle, record the height of the plane and the length of the plane.

8. Using the following formula ( Sin Angle = height / length ) or ( Sin Angle X length = height ) if you have the correct angle measured, then you can use that formula. For example the Sine of 10 ° is equal to 0.174; there for 0.174 X 70 cm = 12.16 cm.

9. Find the height of the plane ; for the following degrees: 20 °, 30 °, 40 °; you can use them in the table if you have the correct degree setting.

MECHANICAL ADVANTAGE OF AN INCLINED PLANE

RESISTANCE	200 g	200 g	200 g	200 g	400 g	400 g	400 g	400 g	500 g	500 g	500 g
ANGLE	10 °	20 °	30 °	40 °	10 °	20 °	30 °	40 °	20 °	30 °	40 °
EFFORT
M. A.
HEIGHT OF PLANE
LENGTH OF PLANE	70 cm	70 cm	70 cm	70 cm	70 cm	70 cm	70 cm	70 cm	70 cm	70 cm	70 cm
I. M. A.

QUESTIONS:

1. What are the two formulas for finding the MECHANICAL ADVANTAGE?

2. How is the angle related to the MECHANICAL ADVANTAGE?

3. The greater the angle the ___________ the mechanical advantage .

4. The smaller the angle the ___________ the mechanical advantage.

5. How is a screw related to an inclined plane ?

6. Give three examples of a double inclined plane.

7. How is a wedge related to the inclined plane ?

8. Why do you have to put more work into a machine, then you really get out of the machine?

9. What is the difference between a simple machine and a compound machine?

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