[Noir Pale]

Noir Pale asked the Naked Scientists:
   
Continuing the question: how hard do you need to pee to knock yourself over... (raised in a discussion arising in this show - http://www.thenakedscientists.com/HTML/podcasts/show/2010.06.27/)

What if you're in space, would it be possible to send your self spinning by simply peeing in the right direction, and if so, could it be possible for astronauts to propel the space ship with it?

In that case it wouldn't it be a good way to save fuel since they need to pee once and a while anyway!

I would love to hear from you, sorry for my poor English, love you podcast.

Best regards

Noir Pale

What do you think?

[neilep]

would they not have to wind down the window and pee out the window for this to have an effect ?...else the urine dump (if they still use such a thing) might have some influence !...I dunno..whajafink guys and gals ?

[Murchie85]

That might be more deceptive that it seems, I know in space firing a gun (assuming air in the chamber) can propel you. Although in the case of peeing im not sure if the the thrust (if any) would not be countered by your body's mechanism that started. Newtons law might be applicable here, any action has an equal and opposite reaction i.e a body can not exert a net force on itself, although the human body might be hard to define as being a single body due to its complexity I still think the net force would be zero.

[Geezer]

It's a matter of acceleration. Because Force = Mass x Acceleration, the more you can accelerate the mass of the "fluid", the greater the propulsive force will be.

I'm pretty sure I could have produced a few newtons when I was five years old. These days, I think we would be in the micro-newton scale.

[RD]

 http://en.wikipedia.org/wiki/Ion_drive