| Elevator Motion Lab |
by Mary Norris, Virginia Tech mnorris@vt.edu
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| Purpose |
To investigate forces, Newton's 2nd and 3rd laws, and free body diagrams
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| Procedure |
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Draw a free-body diagram for a person standing on a scale in the elevator: a) at rest; b) accelerating upward; c) accelerating downward; d) moving at a constant velocity upward or downward.
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Fill in the first two columns (your hypothesis).
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Write the scale readings in pounds in the table when we ride the elevator. Convert these to Newtons (1 lb=4.45 N).
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Record the persons’s weight on your free-body diagram.
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Compute the net force for each part of the elevator ride.
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Compute the person’s mass. Remember that weight in Newtons is mass in kg times 9.8!
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Find the person’s acceleration. (Use F=ma.)
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Write a few sentences that answer the following: If you wake up in an elevator and there are no windows or lights, can you tell if you are moving or not? How?
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| Data |
| Data table |
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Elevator Motion |
Hypothesis
Direction of Fnet and anet
(up, down, zero) |
Scale Reading(N)
(This is the normal force!)
Scale Reading
(more, less, weight) |
Fnet
(N) |
anet
m/s2 |
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1. At Rest |
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| Going Down |
2. Speeding up at top |
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| Going Down |
3. Constant speed downward |
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| Going Down |
4. Slowing down at bottom |
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| Going Up |
5. Speed up at bottom |
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| Going Up |
6. Constant speed upward |
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| Going Up |
7. Slow down at top |
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8. Cable Breaks |
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