A ball is dropped in front of a meter stick and lit by a strobe light. A long exposure photograph captures the position of the ball at each evenly spaced flash of light. The acceleration of the ball can then be measured from the photo.
Note that the frame rate of the video capture (30fps) is quite close to the strobe rate (15Hz). This is why the strobe flashes in the slow motion video don't appear to be exactly evenly timed.
See the final image on Flickr - http://www.flickr.com/photos/physicsd...
See the original video on MIT TechTV - http://techtv.mit.edu/videos/831-stro...
Watch video MIT Physics Demo -- Strobe of a Falling Ball online without registration, duration hours minute second in high quality. This video was added by user mittechtv 23 March 2009, don't forget to share it with your friends and acquaintances, it has been viewed on our site 143,50 once and liked it 39 people.