Question about a fly?

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Gilly said:
:/
Does the air inside the car move at 80mph to avoid being left behind?
No it does not.
It moves with the car.
Gilly said:
When an astronaut is floating in his shuttle in space is he having to hold on to stop himself being propelled through the back wall?
Unless the shuttle has the rockets firing, the only thing thats moving the shuttle is gravity, the same thing that moves the astronaut.
 
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No, the fly would not have to travel at 80mph to keep up with the car.

We had a MASSIVE thread on this a while back, it was rather disturbing.

Ant :cool:
 
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Phnom_Penh said:
It moves with the car.

Only if the fly has accelerated to the same speed as the car. If the fly was not touching any part of the car during acceleration, the fly would have accelerate at the same rate as the car otherwise it will get splatted on the rear windscreen. If the fly is hovering inside the car, it won't magically accelerate at the same rate as the car. If you know how to do that I think you'll have sorted out any energy crisis we may face in the future as you'd be creating movement out of nothing :p
 
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Yeh, flies arnt allowed to touch things, thats why when they are in your car they fly at 80mph, otherwise they align their particles with the cars and just fly straight through the window.

This does depend on the fly. If its the winged fly of uSahStewPeed then your fly should have no troubles keeping up inside the car.
 
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the fly does not have to fly at 80mph to stop it hitting the back window because the air in the car is contained in a relatively airtight bubble, where the air is NOT moving. if you had no front and rear screen then the air would pass through the car and the fly would be long gone.
 
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WantoN said:
No, the fly would not have to travel at 80mph to keep up with the car.

We had a MASSIVE thread on this a while back, it was rather disturbing.

Ant :cool:

The original question lacks a few assumptions. 2 Examples:

1) The car with fly in accelerates to 80mph, if the fly was stationery in mid air, then it would hit the back window unless it sat down until it reached 80mph. Once at 80mph, if the fly decides to fly vertically, then relative to the car, its horizontal motion is 0mph and so does not hit the window.

2) If the fly magically appeared out of nowhere into the car (not moving anywhere). then the cars going to squash the damn thing :)
 
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To add to my point.

Ever had a wasp buzzing around your head in the car? Reckon the little blighter is flying sideways at 80mph just to annoy you?

EDIT: Ok, I was working on the assumption that the fly/wasp was already in the car, and had taken off. Anyhoo :/ This thread has made my brain begin to liquify already.

Ant :cool:
 
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chopchop said:
the fly does not have to fly at 80mph to stop it hitting the back window because the air in the car is contained in a relatively airtight bubble, where the air is NOT moving. if you had no front and rear screen then the air would pass through the car and the fly would be long gone.

Lets say you are standing on top of a car thats travelling at 30mph. You jump vertically. Do you 'fly' backwards???

No!
 
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chopchop said:
the fly does not have to fly at 80mph to stop it hitting the back window because the air in the car is contained in a relatively airtight bubble, where the air is NOT moving. if you had no front and rear screen then the air would pass through the car and the fly would be long gone.

You are making the assumption that the fly has accelerated from a standstill to the speed of the car. Relative to 'space' the fly is travelling at 80mph inside the car and as there is no resistance, the momentum keeps it going. However, if the car accelerated from a standstill with the fly hovering inside, unless the fly accelerates at the same rate as the car, it will splat on the rear.
 
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hendrix said:
Lets say you are standing on top of a car thats travelling at 30mph. You jump vertically. Do you 'fly' backwards???

No!
Depending on how high you jump, yes. As once you lose contact with the car, the loss of momentum and wind resistance will slow you down.
 
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Sic said:
no, but because you're sat on the seat, you're being pulled along by the car, so the car is making you move 80mph. if you were floating in the car and it started moving, i'm fairly sure you'd go through the back window. unfortunately, i cant recreate this to prove it.

technically, yes- but a fly is already exerting force on the air in order to stay hovering- the air in the car doesnt move when you pull off, so neither does the fly...same as you sitting on the seat essentially.
 

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Surely if the fly hovering was to splatter against the back window, that would mean that anything inside the car that was not secured would suffer the same fate. Does that mean if i throw something on to the back seat of a car whilst accellerating, I can expect it to end up 20 feet down the road behind me? I think not.
 
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