Aaron Titus home   |   physics.highpoint.edu /videos/

## Video Analysis

### Camera

Our camera is a Casio Exilim EX-F1. Unfortunately, I'm not sure they sell it anymore. However, at

you'll see the EX-FH25 and EX-FH20 which are similar. They will do up to 1000 frames per second. But notice how cheap they are: \$274-\$349.

### Video Analysis Software

I highly recommend the free, open-source program Tracker (http://www.cabrillo.edu/~dbrown/tracker/) which is well-maintained and supported by the author, Doug Brown, and the Open Source Physics developers. Students can create a theoretical model by defining the force on an object and the initial conditions and can compare the theoretical model with the motion of the object.

For commercial video analysis software, I recommend Logger Pro by Vernier (http://www.vernier.com/soft/lp.html). Its license is a site license that covers your classroom and home computers for you and your students. This allows students to install it on their laptops, for example. Its advantage is that students can use the same software for data collection with sensors.

### Videos

Here are some videos we've used at HPU in our physics labs or for undergraduate research or for demos. For videos not produced at HPU, we list the author and source for the video.

 Constant velocity rolling ball - slow A steel ball rolls with a constant velocity on an aluminum track with negligible friction. Its speed is approximately 0.32 m/s. The length of the track, measured from end to end, is 2.2 m.recording speed: 30fpsarea: Newton's second law; uniform motionvideo credit: Aaron Titus

 Constant velocity rolling ball - fast A steel ball rolls with a constant velocity on an aluminum track with negligible friction. Its speed is approximately 0.53 m/s. The length of the track, measured from end to end, is 2.2 m.recording speed: 30fpsarea: Newton's second law; uniform motionvideo credit: Aaron Titus

 Soccer ball shot from truck - Mythbusters A soccer ball is shot from the back of a truck with the same speed as the truck. Thus, the ball's initial velocity measured by a person on the ground is zero, and it falls from rest. I do not yet have a calibration to use for this video, and I do not know the frames per second of the recording.recording speed: ?area: Relativity; Galilean relativityvideo credit: Mythbusters soccer-ball-shot-from-truck-Mythbusters.mov

 Basketball shot A basketall travels from the player's hand to the floor. Use the 2-m stick on the base of the wall for calibration.recording speed: 30 fpsarea: Newton's Second Law; projectile motionvideo credit: Vernier LoggerPro CD

 Fancart - constant force A fan exerts a constant force on a cart. (The video also shows a second cart that moves with a constant velocity.) The acceleration of the fancart is approximately 0.19 m/s2.recording speed: 5 fpsarea: Newton's second law; constant net forcevideo credit: RIT LivePhoto Physics Series (http://livephoto.rit.edu/)

 Impact force during landing (long dt) A person jumps from a table and lands on the floor. From his motion, the force by the floor on the person can be calculated. In this video, his knees bend as much as possible upon landing.recording speed: 30 fpsarea: Newton's second law; constant net forcevideo credit: Aaron Titus

 Impact force during landing (short dt) A person jumps from a table and lands on the floor. From his motion, the force by the floor on the person can be calculated. In this video, his knees bend a small amount upon landing.recording speed: 30 fpsarea: Newton's second law; constant net forcevideo credit: Aaron Titus

 Collision of two carts A one-dimensional collision of two carts on a track.recording speed: 30fpsarea: Newton's second law; conservation of momentumvideo credit: RIT LivePhoto Physics Series (http://livephoto.rit.edu/)

 Two-dimensional collision of two pucks A two-dimensional collision of two pucks on an air-hockey table.recording speed: 30fpsarea: Newton's second law; conservation of momentumvideo credit: Flashmedia

 Circular motion of a car A car travels around a roundabout. A bobber in a jar of water sitting on the dashboard floats in the direction of the acceleration of the car.recording speed: 30fpsarea: Newton's second law; uniform circular motionvideo credit: Dale Basler (www.dalebasler.com) car-roundabout.mov

 Uniform circular motion of a bicycle wheel A bicycle wheel is held by its axle and rotates with nearly constant speed.The first frame is used to set the calibration. Motion begins in the second frame. The video is recorded at 300 fps but plays back at 30 fps.recording speed: 300fpsarea: Newton's Second Law; uniform circular motionvideo credit: Aaron Titus and Martin DeWitt

 Bicycle wheel gyroscope A bicycle wheel is held by its axle. When released, the wheel precesses. There are two parts of the motion. (1) Before it is released, a point on the wheel is in uniform circular motion and its period and angular frequency can be measured by a sinusoidal fit to x vs. t. (2) After it is released, the wheel precesses. Though it precesses in the third dimension, the axle can be marked every 1/4 of a precession, and x vs. t for the axle can be graphed to determine the precessional frequency . As a result, its precessional frequency can be determined. The video was recorded at 300 fps.recording speed: 300fpsarea: Angular Momentum Principle; gyroscopevideo credit: Aaron Titus

 Pendulum Though the video shows three oscillations, it is easiest to analyze one half of an oscillation. Though oscillations are not very small, angles are small enough that a sinusoidal fit can be used for θ vs. t to determine the angular frequency. This video can be analyzed in a multiltude of ways. For example, τ vs. α is linear, and the slope can be used to determine the moment of inertia of the pendulum. The center of mass is approximately at the location of the green sticker, though closer to the top edge of the sticker.recording speed: 30fpsarea: Angular Momentum Principle; Pendulumvideo credit: Aaron Titus

 Figure Skater Spin A figure skater performs a "scratch spin." Since the net torque on the skater is approximately zero, her angular momentum is conserved.recording speed: 300fpsarea: Angular Momentum Principle; conservation of angular momentumvideo credit: Ashley Press and Aaron Titus

 Coriolis effect - motion of a ball on a merry-go-round A ball rolls on a rotating merry-go-round. In a stationary frame, its velocity is constant witih a magnitude of approximately 1.3 m/s (assuming a merry-go-round diameter of 2 m). You must estimate the diameter of the merry-go-round in order to calibrate distances in the video.This lab is written as inquiry. Students should also download the video corioliskraft.movrecording speed: 30fpsarea: Newton's first law; uniform motion, reference framesvideo credit: Video found on YouTube at http://www.youtube.com/watch?v=LAX3ALdienQ

 Inertial and non-inertial reference frames The video shows an accelerating fancart and a cart moving with uniform motion. By transforming the reference frame to one of the carts, you can measure the motion of the other cart and determine whether you are in an inertial or non-inertial reference frame.recording speed: 5fpsarea: Newton's first law; inertial and non-inertial reference framesvideo credit: RIT LivePhoto Physics Series http://livephoto.rit.edu/