William W. answered • 11/27/21
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Draw a free body diagram:
Where FD is the drag force and FG is the force of gravity.
Terminal velocity means the velocity is not changing, or, in other words there is no acceleration. If ther is no acceleration, then the net force is zero so, summing the forces in the y-direction:
∑Fy = FD - FG = 0
or
FD = FG
But FG = mg and FD = -bv so:
substitute those into the equation, solve for "b", and plug in m = 3x10−5 kg and v = 9 m/s
William W.
mg = -bv so b = (3x10^-5)(9.81)/(-9) meaning b = -3x10^-5
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11/28/21
William W.
Actually, I’m not sure about the negative in the equation. The velocity may need to be negative so perhaps “b” is a positive number. Not sure how they set this up.
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11/28/21
Anjela R.
Okay, thank you
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11/28/21
Anjela R.
i got 7.84x10^-5 can you confirm?11/28/21