Last weekend, the circus came to town, and Grandma and Grandpa came up to help us take the kids. We took SteelyKid a couple of years ago, and figured The Pip was old enough to go this time, too. Having bought tickets a couple of years ago, I got sent a pre-sale offer link, and followed that to get tickets in the front center section.
What I didn't realize was that these put us in the "Circus Celebrity" section-- when the show started, they came and gave us these ribbon things to wear, and a bit before the intermission some of the performers came over to our section, and led us out to the floor, where we rode around in a train of cars as part of one of the musical numbers, and chatted with some of the clowns, as you can see from the "featured image" above.
This also meant we were on the floor for this:
Now there's unquestionably some physics to this, and I had vaguely meant to crank the video into Tracker and try to determine the launch speed, and compare to the stats in the program. I've been crazy busy this week, though, and today's the Steinmetz Symposium with student research presentations all day, so I don't have time.
So we'll make this a homework problem: see if you can use this crappy cell-phone video to determine how fast she was moving when she was launched. Send your answers to Rhett for grading, and I'll see you on Monday.
Assuming its 100m distance, and the cannon is at its optimal angle (45° over horizontal), then the velocity is the same one needs to shoot the person 25m straght up.
v= &sqrt;(g*h) , where h is 25m and g is gravitational acceleration, roughly 9.8m/s².
It's a bit less than 16m/s, or about 36mph.