Don't let COVID get the better of you 7 (dropping small pieces of paper)

Let's take a look!

What type of experiment is this?

Experimental procedure and explanation:

• We compare the falling speeds using pieces of paper cut and rounded to an approximately 2-cm square and pieces of paper shredded into small pieces.
• Two types of paper are dropped at the same time. The larger pieces of paper fall faster. The difference in falling speed cannot be easily observed, but can be confirmed by the fact that the smallest pieces of paper are the last to fall.
•  Don't let COVID get the better of you 6 (drop small objects) This is an experiment similar to the one described in the previous section.
• This result may be attributed to the nature of air resistance and gravity. The magnitude of air resistance depends on the shape, size, and velocity of the object. Because the magnitude of air resistance is approximately proportional to the area subjected to flow (frontal projected area), it is proportional to the approximate square of the size (length) of the object (for example, if the size is twice as large, the air resistance is approximately four times as great).
• On the other hand, the magnitude of the gravitational force acting on an object of uniform density is proportional to the cube of the object's size (diameter for a sphere) (For example, if the size doubles, the gravitational force is approximately eight times greater). In other words, as the object’s size increases, gravitational force increases significantly. The increase in gravitational force is more significant compared to the increase in air resistance. Therefore, for objects of equal density, larger objects fall faster and smaller objects fall more slowly.
• This experimental video was produced with the support of JSPS Grant-in-Aid for Scientific Research 18K03956.

[Keywords]	Ventilation, delamination
[Related items]	Don't let COVID get the better of you 6 (drop small objects), Large ball and small ball 2 (same density)
[Reference]	Ryozo Ishiwata, "Illustrated Fluid Dynamics Trivia", Natsume Publishing, P72-75.

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