Air resistance on a falling person

AI Thread Summary
The discussion focuses on calculating the terminal velocity of a 75.0 kg person experiencing air resistance modeled as proportional to the square of their speed, with a constant of 0.100 kg/m. To find terminal velocity, the forces acting on the person must be balanced, leading to the equation where air resistance equals gravitational force. A free body diagram (FBD) can help visualize and set up the equations needed for solving the problem. For Part B, the air resistance at half the terminal velocity can be calculated by substituting the previously determined terminal velocity into the air resistance formula. Understanding the relationship between speed and air resistance is crucial for solving these physics problems effectively.
garagelu
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If we model the air resistance on a falling person as being proportional to the square of that person's speed, in certain circumstances the proportionality constant between the air resistance and the square of the speed is equal to 0.100 kg/m.


Part A What would be the terminal velocity of a 75.0 kg person?

Part B What would be the air resistance when the person's speed is half the terminal velocity?

I think the wording of the questions is confusing me. Can someone help set this problem up?
 
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The problem is simply telling you that the force of the air resistance is equal to 0.100(v^2). You should check this by doing a dimensional analysis (the units of the force should be Newtons).

garagelu said:
If we model the air resistance on a falling person as being proportional to the square of that person's speed, in certain circumstances the proportionality constant between the air resistance and the square of the speed is equal to 0.100 kg/m.Part A What would be the terminal velocity of a 75.0 kg person?

Part B What would be the air resistance when the person's speed is half the terminal velocity?

I think the wording of the questions is confusing me. Can someone help set this problem up?
 
the terminal velocity occurs when the forces on the person add up to zero (vector addition)

try doing a FBD and equating the forces to each other
then solve for v

for part B, just plug in the value u found
 
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