Gravity question
Discussion
steve-V8s said:
This will be simple for someone that has been to school more recently than me.
Whilst sitting in my armchair I am presumably acted on by a force of 1G. If the floor suddenly disappears I and the armchair will accelerate downwards at roughly 64ft per sec/per sec because of the 1G force.
So if I have a G sensor what will it read before and after the floor disappears.
I guess it will read 1G in both cases but in opposite directions.
Ignoring the 64ft/s/s thing for the moment I feel the other responses in this thread have not taken one factor in to account. It all depends on how far you fall!Whilst sitting in my armchair I am presumably acted on by a force of 1G. If the floor suddenly disappears I and the armchair will accelerate downwards at roughly 64ft per sec/per sec because of the 1G force.
So if I have a G sensor what will it read before and after the floor disappears.
I guess it will read 1G in both cases but in opposite directions.
If there is a hole all the way to the earth's core then you will experience less and less gravitational pull as you continue your increasingly hot journey. This is because you are heading towards the Earth's gravitational centre. Once there, assuming your asbestos underpants continue to function correctly, I'd assume you would eventually "float" in gravitational equilibrium.
TD
No, you'll pass through to the other side of the Earth (assuming the tunnel was a vacuum) - https://en.m.wikipedia.org/wiki/Hole_through_the_e...
The 64ft/s error is the sort of thing that happens when you get old and stupid.
I was considering that if I fitted rockets to my armchair and accelerated horizontally and measured in a horizontal plane a distance of 64ft would pass in 2 seconds if I was achieving 1G so had 64ft on my mind. However that is not the point.
As people have suggested the measuring device I have is an accelerometer.
When measuring in a vertical plane the device will read 1G even though I am not accelerating. When I remove the floor and accelerate downwards it has to read something different, at the centre of the earth the acceleration will stop and after a bit of an overshoot the slightly warm seat will presumably settle in a zero G region, here the reading again has to be something different.
My feeling is it has to read -1G initially as the floor is pushing upwards on the chair , +1G as I fall and the 0G when suspended in the centre.
I was considering that if I fitted rockets to my armchair and accelerated horizontally and measured in a horizontal plane a distance of 64ft would pass in 2 seconds if I was achieving 1G so had 64ft on my mind. However that is not the point.
As people have suggested the measuring device I have is an accelerometer.
When measuring in a vertical plane the device will read 1G even though I am not accelerating. When I remove the floor and accelerate downwards it has to read something different, at the centre of the earth the acceleration will stop and after a bit of an overshoot the slightly warm seat will presumably settle in a zero G region, here the reading again has to be something different.
My feeling is it has to read -1G initially as the floor is pushing upwards on the chair , +1G as I fall and the 0G when suspended in the centre.
V8LM said:
No, you'll pass through to the other side of the Earth (assuming the tunnel was a vacuum) - https://en.m.wikipedia.org/wiki/Hole_through_the_e...
Now you are just being unrealistic! No chance that this hole could support a vacuum. Whereas of course a hole to centre of the earth below an arm chair is perfectly feasible.So I think what I said still stands; you would eventually equilibrate at the centre of the earth - unless you were in a totally unrealistic vacuum!
steve-V8s said:
My feeling is it has to read -1G initially as the floor is pushing upwards on the chair , +1G as I fall and the 0G when suspended in the centre.
The floor pushing up is a reaction force, with no weight what is it a reaction to? If there was an unbalanced upward force of any kind, the chair would move upwards. If the upward force is balanced i.e. standard conditions then there's no movement i.e. no acceleration in any direction.No negative reading...and zero g in freefall, hence the term zero gravity as per the vomit comet etc.
To make it even more interesting have a budgie hovering over some bathroom scales on the chair
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