Determining ball speed, Vernier

[SenorZ]

My team has not built our shooter, but when we do I plan on using the Vernier Video Physics app to get some data on height, range, and speed. Has anyone done the same? If so, share experience, please.

http://www.vernier.com/products/software/video-physics/

[hsekhon27]

If you're using the wheels for shooter, the formula for calculating the tangentional velocity (the velocity of the ball) is 2*pi*f*r, where f is frequency (number of rotations in 1 second) and r is radius of the ball. The formula for calculating the range is (v^2 sin2x)/g, where v is your speed (calculated by 2*pi*f*r), x is your launch angle, and g is 9.81. The formula for a height at a specific range r is r*tan(x)-(g*r)/(v*cos(x))^2. you can rearrange these formulas to find launch angles and launch velocities.

[EricLeifermann]

Originally Posted by hsekhon27

If you're using the wheels for shooter, the formula for calculating the tangentional velocity (the velocity of the ball) is 2*pi*f*r, where f is frequency (number of rotations in 1 second) and r is radius of the ball. The formula for calculating the range is (v^2 sin2x)/g, where v is your speed (calculated by 2*pi*f*r), x is your launch angle, and g is 9.81. The formula for a height at a specific range r is r*tan(x)-(g*r)/(v*cos(x))^2. you can rearrange these formulas to find launch angles and launch velocities.

if your using 9.81 make sure your other measurements are metric as well. So your radius isn't 4 in its 0.1016 meters meters etc...

[SenorZ]

I'm more than familiar with the theoretical speed, range, and height equations. I'm concerned with REAL flight patterns.

The app is an extension of the Vernier lab probe software. Its all about collecting a volume of data to interpret later.

If we get around to it today I'll post a link to the results.

[aheg1220]

We used that software in my physics class to confirm that the acceleration due to gravity is indeed 9.8 meters per second per second.

I think it'll work very well for gathering the data you need.

[commonsense]

Because you are shooting a sphere all kinematic equations will work. However you may want some pro computing if you will be using back spin.

[lcoreyl]

Originally Posted by SenorZ

I'm more than familiar with the theoretical speed, range, and height equations. I'm concerned with REAL flight patterns.

The app is an extension of the Vernier lab probe software. Its all about collecting a volume of data to interpret later.

If we get around to it today I'll post a link to the results.

I have some experience as a physics teacher. The video analysis CAN work well. I don't know what level of precision you are looking for, but I would say if my team was looking to make a long range shooter I would use this tool. Use the best camera you can borrow and use good lighting. The more time you take in setting up your hardware, the better results you will get. Do an analysis of acceleration due to gravity to check how well your setup is.