## The Ramp & Pulley

If Pic and Harry combined the use of an inclined plane and pulley, what mechanical advantage might they gain?

They have set up an inclined plane with a pulley system at the top to help reduce the required applied force.

Talk Now - 2h

With your partner discuss all of the variables available in this type of combined system. (What kinds of things could you change?) List the variables you thought of and explain what each type of change would do to the mechanical advantage. Be sure to answer using complete sentences.

Data Collection::

Select a length for the ramp by dragging the tip of the ramp to the length you choose. Test each of the four possible pulley selections for this ramp and record the information in Table 5 in your lab packet. Select a different length for the ramp and test each of the pulley selections. Record this data in Table 5 also.

In each trial how does the input force compare to the weight of the stone?

Weight [resistance force(3480 N)] divided by effort force equals mechanical advantage. Calculate the system mechanical advantage for each of your tests. The weight in each test is 3480 N. Record your answers on Table 5 in your lab packet.

Select one set of data from Table 5:
1. Calculate the MA of that inclined plane. [ramp length divided by ramp height (1.3) ]
2. Calculate the MA for the pulley system.

Select a second set of data and calculate the MA for the inclined plane and the pulley the same way.

Compare these values with the MA you recorded for these same 2 systems on Table 5.

Talk Now - 2i

Discuss your results with your partner. Using full sentences, describe what happens to the mechanical advantage when you combine simple machines.

Challenge: Design 2 different inclined plane and a pulley systems which will allow Pic and Harry to each raise a stone the same distance while using the same effort forces.