If you're on a stationary (stationery sp...) bus and....?

Question

there's a fly (one that works ;) ) just in front of you...

and also another identical (clone or something) outside the bus at same sort of position.....

Bus starts moving forward....

How come (assuming both flies just hovering) the fly inside the bus stays in same place but fly outide bus has gone way behind you...

How come fly inside bus has not been smashed against inside windscreen

And also how come a third fly minding his/her own business just outside up in front of bus gets smashed on outside of front bus window??

Answer 1

why are you fiddling with your flies pondering physics, well whatever rocks your boat. fly A and fly B are equally distant from one another the bus is an incedental object of greater mass traveling at a proportional speed relative to the moment of static impact. the bus ends up with a micro scratch and some maggots end up as orphans.

Answer 2

Norrie has the right idea.

The fly inside the bus will only stay in the same place relative to the bus if it chooses to fly in the direction the bus is moving. You will notice that when the bus starts moving (whenever it speeds up), you feel the seat pushing against you. That is the force that accelerates you to the same speed as the bus, and when the bus reaches a constant speed, you don't feel the seat pushing against forward on you anymore. The fly is flying, so there is nothing to push it forward. But I've never seen a fly just stay stationary in the air, but if it did, it would move back relative to the bus.

Cheers!

Answer 3

If the bus took off fast enough, the fly would be crushed against the back window. However, if the fly is not crushed it would be because the "body of air" that the fly in the bus is hovering in is contained and brought along by the bus. The fly would be staying in the same position relative to the body of air and the body of air would stay in the same position relative to the bus (in the same way that a "body of water" would stay in the same position inside an enclosed container that was slowly moved).

Answer 4

This is the gateway to relativity - the fly inside the bus is stationary relative to the bus cause it is stationary relative to the air inside the bus which is also stationary relative to the bus. BUT the fly outside could argue that IT is stationary and you and your fly and your air are all moving. Either view is equally valid. Plus, all flies and you are moving a thousand miles an hour due to the earth's rotation, so the none of you are truly stationary - but then the earth is circling the center of the galaxy and hair frying speeds, as is the whole galaxy, so really, there is no such thing as stationary. You always have to say (though we usually assume relative to the earth) stationary relative to WHAT.

Answer 5

1...The fly outside is not contained in the air within the bus.
(Otherwise, if you're in the bus, how come you don't get left behind).
2...The bus moving forward would not send the fly forward and, for the same reason as 1. above.
3. The outside fly is in the way of the bus, the bus will hit it.

(Strange question).

Answer 6

The fly in the bus moves with the air inside the bus.

Answer 7

Its an issue of relativity, if the bus moves at 40mph and the fly is stationary in the bus it is moving at 40mph relative to the outside but at 0mph relative to the inside of the bus.
The air inside the bus and everything inside the bus is travelling at 40mph.

Answer 8

If the bus had been metallic purple, none of these things would happen!
The world would be a much better place if all buses were metallic purple

Answer 9

Double Glazing!

Answer 10

Sorry, to busy watching traffic to keep an eye on the flies !