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G force deceleration (1 Viewer)
- Thread starter henry08
- Start date
ratcher0071
Member
I think an astornaut lies towards the Earth's surface. If you think about it, the force experienced by the astronaut, will make him move back, therefore pushing his eyeballs back into their sockets.henry08 said:
ratcher0071
Member
One book out of how many?henry08 said:
Btw, which book????
Pwnage101
Moderator
yeh..thanks for ur contribution mate - they just want 2 know whether its facing towards the earth or away on re entry, they know the reentry corridor...bradman said:
btw according to my notea, whixh i rememba thoroughly researchin cause i had the same problem, Astronauts face IN THE DIRECTION OF MOTION (ie up) when they LAUNCH, and on RE-ENTRY facce OPPOSITE TO THE DIRECTION OF MOTION, (ie up)
i think bout it in terms of reaction force - we know that on launch the astronauts face up - The Force acting on them is obviously up, so the Reaction force is down - they face up cause the Reaction Force keeps their eyes down
Now , using the same logic, on re-entry, the Net Force is UP (away from earth) as the spaceccraft is decelerating, which means the Reaction force is down (towards the earth) - thus to keep eyes in , astronauts must face UP (Away from earth) so that the Raection force is down
I dunno, like i said its a triky area which i found confusing as well, let us know what u think about my explanation and if u find a better/more correct one
EDIT: after reading ratcher0071's post: yeh thats wat i originally thought ,. but then i discovered its the REACTION FORCE that keeps the eyes in - think about it, we know FOR SURE the astronaut faces up (awway from earth) during lift off, but the Force onm the astronaut is up - what is keeping him down is the REACTION - now with ur post u said " If you think about it, the force experienced by the astronaut, will make him move back" - but wont hte astropnaught be going at say 1000km/h toward sthe earth - as the sapcecraft enters atmosphere it SLOWS DOWN , but the Astronaughts inertia will mean the astronaut feelss the Raection force TOWARDS THE PLANET, and thus must be facing AWAY FROM THE PLANET so his eyes are in - like when ur in a car heading towards a wall and put on the brakes - the nest force on teh car is away from the wall, while we feel a net force (inertia) towards the wall - now let the wall be the earth and the car the spaceship - we are hitting the brakes, so to speak, and thus the astronaught willl feel a nmet force (inertia) towards the planet - he must face away in order for his eye to be kept in place...
ive rambled on, i know, but seriously lets work 2gether to get to the bottom of this once and for all....
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ratcher0071
Member
that seems logicallolokay said:
Pwnage101
Moderator
no joke, i lost sleep over this bak in January...
ratcher0071
Member
My brain has gone fuzzy. I just want to sleepPwnage101 said:
It's the same for take-off and re-entry isn't it?
When a rocket takes off, its acceleration is upwards.
When a rocket re-enters, it decelerates downwards (negative acceleration, if up is positive, rocket is slowing down), therefore acceleration is upwards.
Or to put it simply, the net force acting on the rocket is upwards for both situations.
So you'd be facing the sky both for re-entry and takeoff wouldn't you?
When a rocket takes off, its acceleration is upwards.
When a rocket re-enters, it decelerates downwards (negative acceleration, if up is positive, rocket is slowing down), therefore acceleration is upwards.
Or to put it simply, the net force acting on the rocket is upwards for both situations.
So you'd be facing the sky both for re-entry and takeoff wouldn't you?