Physics question

[SO16_Saint]

Am Sat on a train, bored, on the way to a meeting.

 

Had a though pop into my head and can't fathom the answer from Google.

 

"If you were to jump inside a moving train, would I land in the same place or further back?"

[Whitey Grandad]

Am Sat on a train, bored, on the way to a meeting.

 

Had a though pop into my head and can't fathom the answer from Google.

 

"If you were to jump inside a moving train, would I land in the same place or further back?"

 

In a closed train you'd land in the same place. You and the train and the air inside it are all going at the same speed so there's no relative difference. If you were on a flatbed open-topped rail wagon with the relative wind in your face then you'd end up further back and might even fall on the track behind.

[SO16_Saint]

Ah ok, so it's to do with the air around you as much as the movement of the train itself.

 

So what about a travelattor (in airports for example). If you jump, the spot you were stood on would be different to where you land??

[badgerx16]

Ah ok, so it's to do with the air around you as much as the movement of the train itself.

 

So what about a travelattor (in airports for example). If you jump, the spot you were stood on would be different to where you land??

Assuming you are standing still, relative to the travelator, at the moment you leave the ground you are travelling at the same speed, and in the same direction, as the travelator so when you come back down you will have travelled an equivalent distance. If, however, you were to hover above the travelator you would begin to experience resistance from the air, and would begin to lose ground relative to the point you started.

[trousers]

Bear in mind that none of what we experience is real. We're characters in someone's dream and thus a figment of imagination.

[Doctoroncall]

No, it's relative velocity which is both the same for you and the train (i.e the same force).

 

If the train was accelerating and you jumped would you land at the same place?

[Lighthouse]

No, it's relative velocity which is both the same for you and the train (i.e the same force).

 

If the train was accelerating and you jumped would you land at the same place?

 

No, it's all to do with inertia. You will maintain the same velocity until a force acts upon you to change that velocity. Once you jump in the air, the force of the train engine stops acting on you, so you will maintain the same velocity whilst the train continues to accelerate. The net effect will be you move backwards relative to the train.

 

Of course in this situation the air inside the train will continue to accelerate, so instead of air resistance then air will be pushing you forward and cause you to accelerate, albeit by a completely negligible amount.

[saint si]

How about... I'm stood on the surface of earth... moving around the sun at 67,000 mph. If i jump up, do i land in the same place?

 

Velocity is a relative concept... something is only considered moving relative to something else (frame of reference).

 

So as far as you versus the train, you have zero velocity (assuming train is not accelerating, which also means it is not going round a corner)

 

Now consider that the "moving" train is stood still and the earth is moving (rotating) underneath its wheels...

[Whitey Grandad]

Ah ok, so it's to do with the air around you as much as the movement of the train itself.

 

So what about a travelattor (in airports for example). If you jump, the spot you were stood on would be different to where you land??

 

The travelator is carrying you forward against air resistance but as long as your feet are on the moving belt your speed will be the same. If you were to jump vertically then for the short time that you are off the floor you will slow down very slightly due to air resistance and land very slightly behind your original position. Such behaviour is probably against saftey rules.

 

Now try this one:

 

A lorry is carrying a load of chickens (or budgies or any bird with wings) in wire cages and approaching a weak bridge. If the birds are alarmed an flapping their wings will it reduce the load on the lorry's axles?

[Wurzel]

Am Sat on a train, bored, on the way to a meeting.

 

Had a though pop into my head and can't fathom the answer from Google.

 

"If you were to jump inside a moving train, would I land in the same place or further back?"

 

Maybe on the way back from the meeting you could actually try it and let us know what happens.

[Big Bad Bob]

Am Sat on a train, bored, on the way to a meeting.

 

Had a though pop into my head and can't fathom the answer from Google.

 

"If you were to jump inside a moving train, would I land in the same place or further back?"

 

Google "Inertia" will tell you all you need to know...

[Whitey Grandad]

Google "Inertia" will tell you all you need to know...

 

If you can ever be bothered to get round to doing it

[sadoldgit]

Maybe on the way back from the meeting you could actually try it and let us know what happens.

 

Noooooo don't do it. People will think you are a looney!