1. FILTER DRAG LAB By: Rachel H. Buckland and Thomas H. Campion

2. Background and hypothesis Whenever one attempts to measure the acceleration of an object due to gravity they run into the problem of air friction. If given enough time or a small enough mass the object will reach terminal velocity. This means there is no acceleration or change in velocity. In this lab we are attempting to verify our hypothesis which is that we can find the value of n (a drag ) to within +/-15% error as well as the terminal velocities of the filters. We conducted the experiment with multiple different mass while keeping the surface area of drag the same. We did this to see if the results would vary with differing mass, which they should not based upon the equation for the force of drag. Hypothesis is THE KEY point of the lab, give it a slide. This isn’t understandable, it is rambling

3. Methods and Materials  Cassio Ex- FH20 Camera  GoMotion Sensor  Coffee filter stacks d=.205m  Meter stick  scale  Weighed 5 stacks of coffee filters  Dropped filters- GoMotion measures V t  Filmed run, uploaded to LoggerPro, found V t  Found F d = mass of coffee filters times g

4. GoMotion LoggerPro Graph

5. Tommy dropped the filter and its motion is measured by GoMotion which is being controlled by Rachel offscreen. We were dropping 8 filters in this particular picture. Run (5) Picture

6. Experimental Set-up GoMotion camera Coffee filter Meter stick stool student

7. Calculations  F d terminal = mg  K = ρ C d A  C d =.47, ρ = 1.204, A=.033m 2  F d = kv n  lnF d − lnK = nlnv  lnF d =nlnv +lnK  y = mx + b Should this be subscript? F d terminal Units on  K or k or what?

8. Data F d is measured in N (newtons). V t is measured in m/s.

9. Video of Run 5

10.  GoMotion Graph Slope of N N or n?

11. Data of Video Analysis

12.  LoggerPro Graph Slope of N

13. Analysis K calculated is equal to.00933 units/meter, where as the measured are 0.012142 and 0.013507 for the GoMotion and Video Analysis respectively. The K for the measured was the Y-intercept of the graphs in the previous slides. The percent errors for the K are -30% and -45% for the GoMotion and Video analysis respectively. 5 sig figs?

14. Propagation of error  LoggerPro dot inconsistency  Δ V t =.1, V t = 2.663  Propagated error 3.76%  Meter Stick measurement  Δ d =.1, d = 1  Propagated error 10%

15. Ways We Can Improve  Meter stick line up clearer  Clearer video picture with darker background to get more precise loggerpro dots This means to show it clearer or line up vertical?