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Until this point we covered Newton's three laws of motion. And instead of a cotton ball, we used a coffee filter.

*"Our reasoning is this: Each air molecule, on impact, imparts a small force to a falling object. Using the traditional force formula F = ma (Newton, 1687), we see that each collision effectively reduces the gravitational acceleration of any object falling through air by an amount that is inversely proportional to that object’s mass (i.e., a = F ⁄ m ). Thus the light cotton ball is slowed more than a comparably sized (and heavier) rock."*

## Homework Statement

Since coffee filters fall slower than the rock since it is lighter, then we should modify the formula for distance s fallen in time 5. Instead of s=1/2gt^2,

the correct model for falling cotton should be s=1/2kt^2 where k is an acceleration smaller than g.

Confirm or deny this.

(we suggest that the effect of air resistance is greater on the coffee filter because it is lighter)

You have a coffe filter, meter stick, stopwatch, motion sensor, and a x/t and v/t graph.

## Homework Equations

F=ma, ay=1/2at^2

## The Attempt at a Solution

We did this lab today but my partners and I were stumped and likely performed an incomplete or probably unrelated experiment.

We initially thought we should experiment on the effect of surface area on how fast the filter will fall on the ground. But after talking with my other two partners, we just decided to experiment on the effect of increased mass on the rate of falling.

What we did was we used the motion sensor to record the position and velocity over time of initially one coffee filter on a fixed height. Then we added a coffee filter on the first filter to increase the mass. We did this one more time so the last trial was recording the x/t and v/t of 3 coffee filters layered on one another.

What we found was the v/t got more leveled and less steep. From this, we figured that as we increased the mass of an object, it was more able to overcome the force of air resistance as it falls on the ground so "k" approached closer to "g" instead of "k" being an acceleration smaller than "g."

I feel as if that our experiment didn't properly address the fact that regardless of mass, whether the coffee filter is lighter, it should still fall at the same time as a rock.

What did we miss and how could we have done this experiment better to address the fact that even though the coffee filter was lighter, s=1/2gt^2 should still apply and that g SHOULD NOT be changed to "k" which is a smaller acceleration than g?