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If a fly is trapped inside a moving car does it have to fly as fast as the car is travelling?

If a fly is trapped inside a car doing 80mph and the fly is flying around inside the car, is the fly flying 80+ mph just to keep off of the back glass?

12 Answers

  • 1 decade ago
    Favorite Answer

    No. The key for how to think about your question relates to a thing called "relativity and frame of reference".

    For example, relative to an observer standing on the side walk watching the car go past, the fly is in fact moving at 80 MPH relative to that observer. But, relative to an observer's frame of reference while seated inside the car, the fly is just buzzing around at a few feet per second (very slow as compared to 80 MPH).

    And with regard to needing to move at 80 MPH to "stay off the back glass"... Since the predominant "frame of reference" is the car, and since the car is affected by effective 80 MPH wind resistance while the fly is not, the fly has no risk of being crushed against the back glass. Unless you get sick of the pest and smash him with a magazine.

  • Anonymous
    5 years ago

    I has been correctly explained by many (and other times and in other languages even in YR), ... but what do those who answer NO mean? "Does it mean the mosquito is travelling at 100 mph?" YES !!! What is the doubt? If we're travelling at that speed, the mass of air within the car too, the mosquito is inside the car, then also IF: > we use the same system of reference for our speeds (car @ 100mph, those inside also referred to the same system); > consider the mosquito flying slowly and mantaining distance to the car windows, seats etc. (meaning, we neglect its Δspeed to car objects and persons within); THEN the mosquito IS travelling at 100 mph too. Example: we're travelling from NYC to Wahington DC in a car. There's a mosquito bugging inside. If the mosquito's average speed had been zero after arriving in Washington he would have stayed at New York. Regards. . . Outside/inside??? The speed is defined in reference to coordinates, if they're the same for the car and passengers we cannot say the car moves and the passengers (bugs included) don't. Again, if we go to another city in a car only the car travels and we stay at home? If we go in another car at the same speed, but this other car is not ours, then since we´re outside our car we move, but if we're inside it no?? Ridiculous !!

  • 1 decade ago

    no i dun think so. I alwaes see trapped flies bugging me around when im driving some 80+ mph so it is not reallie that the fly have to be 80+ mph to not stick to the back glass...will it be any possible for a fly to be flying that fast?

  • 1 decade ago

    Well if u have to ask and you dont already know then you should just get a car, put maggots in it, and when 1 of the maggots evolves into a fly, get on the autobahn and do 80 and see for yourself using one of those new fly spedometers they just made a few minutes ago and your problem will be solved. if u find out the answer, email me at WWW.URARETARD.COM . thank u please come again. JK :~ )

  • 1 decade ago

    Only if the car is a convertible with the top down. But then I don't see in what sense the fly is trapped.

    This question is seriously so stupid it hurts.

  • Mark P
    Lv 5
    1 decade ago

    No, when we are in a vehicle, we adopt its rate of speed and if we are moving, we add that rate of speed. So a fly in a car is going the speed of the car plus the speed it's flying.

  • 1 decade ago


    Have you ever tried throwing a piece of paper in the car while the car is moving?

    does tat piece of paper slap your face when your running 120 kmh?

  • ?
    Lv 5
    1 decade ago

    Inertia, dingus. Go rent "Explorers" with River Phoenix.

  • 1 decade ago

    No. When you stand up in the car, do you have to run to keep up with it?

  • 1 decade ago

    ground is no airspeed inside the car...

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