Terminal velocity for big objects

AI Thread Summary
The discussion focuses on determining the terminal velocity of large objects like cars and planes, where the drag force is proportional to the square of the velocity. The key formula derived for terminal velocity is Vterm = mg/b, where 'm' is mass, 'g' is gravitational acceleration, and 'b' is a characteristic dimension related to the object's shape. Participants express confusion about the initial setup and calculations, particularly regarding the inclusion of a square root in the equation. The conversation highlights the importance of understanding the relationship between drag force and gravitational force at terminal velocity. Overall, the thread emphasizes the need for clarity in applying physics equations to solve for terminal velocity.
cleverfield
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Homework Statement



The drag force on large objects such as cars, planes, and sky divers moving through air is more nearly Fdrag = -bv^2.

For this quadratic dependence on v, determine a formula for the terminal velocity vTerm, of a vertically falling object.

Express your answer in terms of the variables m, b, and appropriate constants.

Homework Equations


Vterm = mg/b


The Attempt at a Solution



No idea how to begin this question.
 
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At terminal velocity, the force of drag is equal to the gravitational force.

F_{drag}=-bv^2=...
 
'b' is a characteristic dimension, such as the distance from front to rear bumper for an automobile attempting to fly.

You managed to leave out a square root in your equation.
 
Phrak said:
'b' is a characteristic dimension, such as the distance from front to rear bumper for an automobile attempting to fly.

You managed to leave out a square root in your equation.

Which equation?
 
cleverfield said:
Which equation?

From the one meta kindly put up
 

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