Vernier Tech Info Library TIL #1141

Question

How are velocity and acceleration calculated when photogates are used?

Answer

When photogates are used to study the motion of an object, the velocity and accelerations are calculated with a different algorithm than the algorithm used for motion detector data. The reason for this difference is that motion detector data is recorded with uniform time intervals. When studying accelerated motion with photogates, the time intervals are not uniform. An excellent article describing this situation can be found in the April, 1997 issue of The Physics Teacher. The article written by William Leonard is entitled "The Dangers of Automated Data Analysis". The article describes a different way to calculate velocity and acceleration when photogates are used. This calculation is used in Logger Pro software, Palm handheld software, and our calculator-based software. Please contact us if you want us to send this article to you.

Created by: rsorensen on January 29 2003
Last updated by: jhopkins on December 12 2005