Fly in Truck: How Can Flies Fly at High Speed?

[uprootedferre]

1hey i had a question... my friends and i were pondering... there was a fly in my cab of my truck and we were doing like 40 mph with the windows up and the fly was flying around in the cab...

i was wondering why the fly wasnt being pushed back towards the back of the truck and why it was able to fly around the cab of my truck

 

[mikehibbert]

I would imagine it's simply because all of the air in the cab is also moving along at 40 mph.

i.e. inside the cab is a stationary frame.

As long as the cab isn't accelerating (traveling at a constant speed), you don't feel any force inside the cab. If you were in a sealed box (so you couldn't see outside at all) moving at exactly 40 mph, you would have no idea if you were moving or stationary.

I hope that made sense! It did in my head, but I had a hard time explaining it haha.