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Imagine that an object is falling throug...

Imagine that an object is falling through a long straight glass tube held vertical, air has been removed completely from the tube. The object does not touch the walls of the tube. Will the object experience any force of friction?

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No, the object will not experience any force of friction because force of friction takes place only when two surface comes in contact. It is given that the object does not touch the walls of the tube thus, there will be no force of friction.
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