Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Bird Velocity and Acceleration
Name: Gavin F.
Status: educator
Age: 20s
Location: N/A
Country: N/A
Date: 
Monday, September 30, 2002



Question:
I would like to know of a way of measuring the speed and acceleration of flying birds. This would appear to be a straightforward problem but on reflection it is not so easy! In practice radar or laser guns would be difficult to operate and would require the observer to know to angle from bird to device at all times. Using video to measure the time taken for a bird to pass between points a known distance apart would give a measure of speed but not acceleration. So what is the answer, wind tunnels? Is there a simple answer I am missing. Help!


Replies:
Gavin,

The acceleration of a bird will not be constant, so you have to determine what interval of the flight you wish to measure it for (what you will get is average acceleration over that interval). However, measuring the time of flight for a known distance via video can get you acceleration as well, by breaking up its travel into smaller pieces.

Speed = change in distance/time
Acceleration = change in speed/time = (final - initial speed)/time

First we have to assume that you can get a decent measure of speed- you have known points and the bird flies more or less in a straight line between them. The timing between frames of a video should be constant, so if you have good indicators of distance, you can determine speed for any part of the flight by the distance travelled between frames.

Measuring acceleration from rest is the easiest, since you know initial speed is zero. Measuring from other points will be more difficult, depending on your ability to measure distance and speed accurately from the video.

Don Yee


Click here to return to the Zoology Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory