Science Buddies: "Ask an Expert"

I'm doing a science fair project on birds flying in v- formation. The project is listed in Science Buddies. In the experiment I'm using Legos to build the birds. In the instructions there is a base plate that your birds are connected to that is 6o cm from your wind source, I'm using a regular box fan. My question is, why is the base plate 60cm from the fan? I'm just curious because it might be a question my teacher/interviewers might ask me. Is there a specific reason on why the base plate is 60 cm from the fan?

Hi Legato,

I read the Procedure for the V-formation project and I don't know why the person who designed this project picked 60 cm for the distance between the fan and the base plate. My guess would be that it was arrived at empirically by testing different distances and measuring the effect on the 'bird'. In a wind tunnel that is used to test the aerodynamics of various structures, the source of the wind is some distance away from the model but it is also very powerful. The fan in this experiment creates the 'wind tunnel' and has to be close enough to provide sufficient air flow and lift but not so close as to produce turbulence and erratic effects.

Maybe the person who created the project will see your post and can provide you with the correct answer to your question. But you are a scientist, now. You had the curiosity to ask this question, and that is one of the best traits a scientist can have, so why don't you answer your own question by testing it? Place the fan at 10, 20, 40, 60, 80 and 100 cm away form the plate and measure the effect. Maybe with your particular experimental set-up, 60 cm is not the best distance.

Have fun and let us know what happened!

Best wishes,

Sybee