# Problem 9.2 Classical Mechanics: Astronaut in a rotating space station

## Homework Statement

Acceleration experienced by an astronaut in a rotating space station.

## Homework Equations

What force would he experience is his own rotating frame of reference.

## The Attempt at a Solution

Newton's second Law for a rotating frame is:
mr'' = F net+ Fcor + Fcf
Fnet (In the innertial frame) = ma_c (centripetal acc)
Fcor = 2m(r'xΩ)
Fcf = m(Ωxr)xΩ

I saw online that the answer was just the centrifugal force since the astronaut feels like he is being pushed away. However I do not understand why is it only that one and not Fcor + Fcf , so I am confused on how to understand the motion. From his view, he is not moving (the station wall is pushing back on him) which I would think of that to be Fnet , but if he isn't moving in the rotational frame so what is the acceleration r'' describing.

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PeroK
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## Homework Statement

Acceleration experienced by an astronaut in a rotating space station.

## Homework Equations

What force would he experience is his own rotating frame of reference.

## The Attempt at a Solution

Newton's second Law for a rotating frame is:
mr'' = F net+ Fcor + Fcf
Fnet (In the innertial frame) = ma_c (centripetal acc)
Fcor = 2m(r'xΩ)
Fcf = m(Ωxr)xΩ

I saw online that the answer was just the centrifugal force since the astronaut feels like he is being pushed away. However I do not understand why is it only that one and not Fcor + Fcf , so I am confused on how to understand the motion. From his view, he is not moving (the station wall is pushing back on him) which I would think of that to be Fnet , but if he isn't moving in the rotational frame so what is the acceleration r'' describing.
If he is at rest then ##\textbf{r}''## ##=0##. Also, since ## \textbf{r}'## ##=0##, the coriolis force is zero.

SebastianRM