If a person drops a stack of 5 coffee filters and then a stack of 4,3,2,1 coffee filters. Will the drag force increase, decrease, or remain the same throughout this? Can someone please explain?

Question

mrnood · Answer

I assume you mean the cone shaped filters that fit inside each other

drag force has th following equation:

$$F _{d} = \frac{ 1 }{ 2 } \rho u ^{2} A \times C _{d}$$

Now - the coefficient of drag and the Area or essentially dependent on the shap of the object as presented to the air

you can see that the stack remains essentially the same shape however many filters are stacked

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so - looking at the formula - if you approximate A and Cd are the SAME for all stack - what can you say about the Fd?