Here's a Question!
Dictionary vs. Styrofoam Cup
A dictionary and a styrofoam cup are dropped from roughly the same height. The dictionary falls faster than the styrofoam cup. What happens if the cup is placed on top of the dictionary and they're dropped together?
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Joanna and Steve: Just science!
Joanna: Hi! I'm Joanna!
Steve: And I'm Steve!
Joanna: Here's a question for you...
Steve: A dictionary and a styrofoam cup are dropped from roughly the same height.
Clearly, the dictionary falls faster than the styrofoam cup.
Joanna: What happens if the cup is placed on top of the dictionary and they're dropped together?
Does the dictionary fall quickly and the cup fall slowly?
Steve: Does the cup fall quickly and the dictionary fall slowly?
Joanna: Do they both fall quickly?
Steve: Or, do they both fall slowly?
Joanna: Pause the video now if you'd like to think it over before we show you what happens.
Joanna: Air resistance has a greater effect on the styrofoam cup than on the dictionary. If we could drop them in a vacuum, both the cup and the dictionary would fall with the same acceleration.
Steve: Now, fortunately for us... or, maybe unfortunately... we don't have the ability or the budget to place this room under vacuum. But, we can do our best to remove air resistance for the cup by placing it on the dictionary. The dictionary acts like a windshield so the cup doesn't see a 'wind' as it falls.
Joanna: Once air resistance is effectively a non-issue, both the cup and the dictionary fall together.
Thanks for watching. I hope you'll join us again soon for another question!
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