SaraD-Vterminal-PennyvDollar

I believe that the Dollar Coin is more dangerous than the penny (it will have a higher Vterminal). I base this hypothesis on the weight of the coin. I held both in my left hand separately and the Dollar Coin appears to be of more 'weight', more mass and a higher density. These factors are likely to foreshadow the more dangerous of the two coins. These coins are likely to have a close-to proportional ratios for their weight/surface area/speed.

On second thought, I predict the penny to have a higher terminal velocity. I changed my mind because I believe the ratio of the dollar coin's weight:surface area will be greater than the penny's. I think the Dollar coin's density(mass and volume) will be a disadvantage to its terminal velocity.

Monday 9 February 2009

I would prefer that you pick one of these to do; not all three! a) Yes. The chip clip is the most accurate way to make sure the two coins drop at the same exact moment. Also, the coins' bottom curves must be equal with the clip's edge. b) We will film the approximate 4 meter drop to see which hits first. We only film the frame of the floor and a few inches above it to see which hits the floor first. c) The same as above, we will film only within the frame of where the coins will land.**
 * 1) Dropping to see which falls faster.

2) Dropping to see which one hits harder. a) Styrofoam because it is easily impacted upon. Seeing which has greater force will be virtually easier. b) Four meters. c) Yes, it should be fairly easy but may take a few tries for both coins to hit it on one try. d) Judging by the indentation of the styrofoam I will know which had a greater impact, all the same, I will know which coin hit harder.

3) Researching weights and areas. a) Wikipedia articles, most accessible. b) Area of a circle= pi(r)^2, r=1/2d. pi is a constant. Plug the values in and voila! c) Once I obtain the weights and areas of the coins, I will compare the coins' surface areas and weights and estimate the terminal velocity based on these factors. I will divide the areas by the weights. (Weight/SA)

We chose to do the First experiment. Philip stood about four meters above me and dropped the coins while I was at the base level filming the drop to see which fell fastest.

I am at home and not able to submit my video to the UMtube site, where I planned on embedding a link to the video here for you to watch the drop. The coins hit the ground at about the same time. Their speed made it very difficult to decipher, so I opened it in quicktime and did a frame by frame analysis. In the beginning of the video I indicated which side of the screen each of the coins would fall on and that is how I would decipher which coin fell first.

Above is a screen shot of our drop. It is very hard to see here, so I inserted arrows using graffle pointing to the two different coins. The lower one (which is actually the higher one because we filmed this upside down to get the best angle) is hte dollar coin. It is higher because it has already hit hte ground and has bounced up. The penny is lower because it is just about to hit hte ground for the first time. Above is a screenshot of the penny falling. The dollar coin already bounced away.
 * this indicates that the dollar coin falls faster. Although by ONLY miniscule fractions of a second. It seems like more in this screenshot because I was going frame by frames at milisecond speed. Based on these results, if the cons were dropped simultaneously off of the Empire State Building then perhaps the dollar coin would have more of an impact because its free-falling speed is greater.

To compare to other groups: Here below is another group's experiment. You can see that their dollar coin (closest to us) fell first, before the penny as well.

A conclusion we could make about the air drag is that the air drag although, we expected the dollar coin's air drag to be greater, had little affect on the outcome of this experiment. The other factors were more significant.