Foam rubber ball hanging in a string - Forces

AI Thread Summary
The discussion centers on a physics homework problem involving a foam rubber ball suspended by a string in front of a fan, creating an air flow that causes the ball to deflect at a 38-degree angle. The drag force acting on the ball is given by a specific equation, and the user seeks help in determining the speed of the air flow affecting the ball. Participants confirm that the user has correctly identified the forces acting on the ball, including gravitational force, wind force, and tension in the string. They advise adding these forces as vectors to ensure their sum equals zero and remind the user to convert the mass from grams to kilograms. The conversation highlights the importance of understanding force diagrams and vector addition in solving physics problems.
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Homework Statement


Okay, so I'm not originally an English speaker, so this may be silly reading for some of you, especially a lot of the words here, which isn't to find in the dictionaries either, but hopefully you'll at least get a picture of the task and help me solve it.

The drag (air resistance) of a ball made of foam rubber, is:
L = (8,7 \cdot 10^{-4} Ns^2 / m^2)v^2
The ball has a mass of 8,0 g.

We attach the ball to a piece of string hanging from the ceiling, and in front of a reversed vacuum cleaner. LOL. I have no idea what to call that machine in English, but it creates an air flow the affects the ball when it's hanging there in midair.

The air flow makes the ball move to the side, so that the string makes an angle of 38 degrees compared to straight down.

Draw an illustration showing the forces affecting the ball. Find the speed of the air when it passes the ball.


Homework Equations



I mentioned the only equation earlier, I think.

The Attempt at a Solution


No idea how to start. As for the drawing, I've written the gravitational force G straight down, the wind force V directly right and the string force parallel to the string, going from the ball. Is that correct? Anything else?

Thanks a lot.


Edit: I guess I could have called that "machine" a fan, and made it easy for myself. Lol.
 
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You have drawn the forces correctly. Now all you have to do is add them as vectors and say that their sum is zero. Don't forget to convert the mass from grams to kilograms.

** Edit **

A "reverse vacuum cleaner" is perfectly understandable.
 
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