Materials needed for the prosthetic arm activity (adapted from Teaching Engineering
8
):
Each group: one meter stick, scissors, prosthetic arm structural materials (different for each group), a 10kN spring scale
Each student: Prosthetic Party Worksheet – adapted from Teach Engineering.
Entire class: 1 roll of duct tape, one or two 5lb rice bags
Suggestions for the structural material for the prosthetic arm:
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For arm structure: 46 cm long plastic or metal pipes, unused toilet plungers, cardboard tube (from wrapping paper or paper towel roll), wooden "2 x 4"
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For comfort: large sponges, scrap bubble wrap, scrap cardboard, etc
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For lifelikeness: bath towels, shirt or T-shirt, gloves (use students')
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For body attachment: String, rope, twine (about 30 ft [or 10 m])
Classroom activity – How strong is your biceps
This would be an extension activity of either the Prosthetic arm activity or of the Example 1 from the Classroom activity – Classical problems activity presented before. It is an inquiry-based activity in which students will have a choice to work alone, in pairs or in groups. Their task is to set up an experiment by which to measure how strong is their biceps muscle (in N or lb). Upon completion of this activity they will present their findings to the class. The class can challenge the presenters' findings using Physics content knowledge. There are a number of question that can be addressed at the conclusion of this activity. One question is if there is any correlation between the strength of the muscle and its circumference and between the strength of the muscle and the heaviest weight the student can lift. One should expect the strength of the muscle to increase with increasing the circumference of the muscle and the strength of the muscle to be about seven times bigger than the heaviest weight the student can lift?
