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Weight change in rotating space station

  • Thread starter indie452
  • Start date
1. The problem statement, all variables and given/known data

station has radius 25m and rotate with w.
we were asked to find the period of rotation required to produce apparent gravity 0.7g i worked this out to be 11.99s = 12s. using a(0.7g) = v^2 /r

we are then asked if astronaut weighs 75Kg and runs at 5m/s in the direction of rotation what is his apparent weight?

3. The attempt at a solution

I know the weight will increase but im not sure by how much

i tried finding the coriolis acc. = 2wv' v' is velocity in rotating frame
this is relative to the centrifugal force (which in this case is 0.7g) so i divided by this amount and got:

2*2pi/12*5 = 5.24m/s/s
5.24/0.7g = 0.763

i was wondering if this means that the weight increases by 76% so it changes from:
before = 75*0.7g = 515.025N
after = 907.98N

i thought this might be too much but then again he is running at 5m/s
is this right?
ok ive looked through some of y books and found that it says that for a guy standing in a spinning wheel the apparent weight i m*w^2*r and so i thought that i could just change w to be w[o]+w[5] where w[0] is him still and w[5] is him running at 5m/s

so apparent weight = 75*(0.524 + 0.2)^2*25 = 982.83N


is this right? cause it seems ore logical

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