cq_1_231

Phy 231

Your 'cq_1_23.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

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A wad of paper is dropped from a second-story balcony and falls through still air to the ground.

• As it speeds up, what happens to the air resistance it encounters?

answer/question/discussion: ->->->->->->->->->->->-> :

As the wad of paper speeds up, the air resistance does more work against the paper. This is because the wad of paper is increasing its speed, thus increasing its energy. To counter a greater energy, a greater work must be done.

• What happens to the net force acting on it?

answer/question/discussion: ->->->->->->->->->->->-> :

If it is accelerating at a constant rate downwards, I would assume that the net force remains the same. Proportionally the forces acting on it would change I guess, but the net force would remain the same. I'm not so sure.

• What happens to its acceleration?

answer/question/discussion: ->->->->->->->->->->->-> :

I would think the acceleration remains a constant 9.8 m/s^2 because of gravity. Air resistance would affect this so maybe its velocity would increase at a decreasing rate.

• If it dropped from a much higher point, what would happen to the net force and the acceleration?

answer/question/discussion: ->->->->->->->->->->->-> :

Its acceleration would be 9.8m/s^2 until it reaches its terminal velocity. This is the point at which its velocity can increase no longer because of air resistance. I don't know what happens to the net force. It still would be downward since the paper wad is falling downward, but I don't know how it would change.

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25 min

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Net force decreases, approaching zero if the object falls far enough. See the discussion at the link:

&#Please compare your solutions with the expanded discussion at the link

Solution

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