Pulleys!

Laboratory five is a fairly simple investigation of the use of pulleys to demonstrate mechanical advantage. This laboratory is the weakest in terms of tying into the lecture-demonstration section. The week focuses on force, but from a motion and Newton's laws perspective. A force equals mass times acceleration laboratory would be more appropriate, but I have not seen a good local materials only system that well illustrates the principal. In my head I think of wagons being accelerated by spring scale systems, but I have yet to conceive of a practical rig. Ideally one would vary the mass for a constant force and obtain a linearly varying acceleration, but short of air tracks and carts I have not come up with the rig to demonstrate the relationship using locally available supplies.

Sharisey Lee Ling hooking up a spring scale to measure force

Petery Peter changing the load on her pulley

Macy Johannes records data as Callany David looks at other groups

Mary-Ann Lekka rethreading the upper pulley

Petery working with Veralyn Celestine

Mary-Ann making a spring scale reading

Monaliza Mauricio records data

Erika Billen changes masses as Casan-Jenae Joab reads the spring scale


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