Why dont flys wack the rear screen of a car on the highway?

Question

if you have a fly in your car and doing 90 on the highway, how come the fly dont wack your rear screen when it flies around the car? i'm assumin its cause of an air vacuum. but if you open the windows, they still fly around as long as the wind dont push them.or if you throw a ball in the air on a travellin bus. it still falls into your hands even though you would have travelled a few metres forwards.this is probably a really daft question but i remember askin my science teacher in school and he just sort of ignored me.appreciate it

Answer 1

Why don't raindrops hit the underside of the umbrella?

Answer 2

For the same reason that when you jump as high as you can, you land on the same spot, even though the earth is spinning at roughly 1000 miles per hour...

The atmosphere forms an envelop, which you, and all the flies, and all the birds, are part of...

Answer 3

the fly is traveling at the same speed as you are.  why don't you smack the rear window at 90.

Answer 4

"Mythbusters" explored the urban legend that a truck weighed less when a cargo of birds were flying as opposed to sitting on their perches. Some of the same things apply.

You're in the car and the driver slams on the brakes. You fly forward due to inertia. The car has stopped but your still moving at speed. Smack on the windshield (should have worn that seat belt) However the fly that was buzzing you is still there.

Pardon the non scientific answer. "Physics" is the place to post this question for that kind of answer. First, the fly is very light so inertia doesn't effect it that much. It's terminal velocity is much lower then yours. Second the fly is effected  buy changes in speed. However watching the thing and seeing the minor changes is hard.

As for the ball on the bus, try doing it over a longer distance when the buss is changing speed. When you toss it across the bus and the bus (and you) are moving the same, the ball doesn't curve very much (short distance, low speed) Plus we humans are pretty good at judging motion. Toss the ball to your friend, they will probably be able to adjust to the speed.

Do a "Mythbuster" test. Take one of those spinning playground toys, make a device to toss the ball consistently and try hitting a target at different speeds. Bet the teacher would buy into extra credit

Answer 5

well, it's basically inertia. the same thing that keeps you from smashing into your rear window keeps the fly for doing that. the car is a "sealed" environment, the air and it's movements are independent from what happens outside (unless, of course, you open the window, as you said).

as for the ball in the bus, it preserves its speed and direction, just as you do (see principle of inertia, which is basic in Physics).  the same inertia has you "flying" towards the front of the bus when the driver brakes abruptly: you tend to preserve direction and speed, but the reference system (ie the bus) changes its speed.