[Emil Rayfield]

Emil Rayfield asked the Naked Scientists:

Why does your stomach get left behind when a lift or airplane drops?

From Emil (aged 7), Dubai

What do you think?

[Simulated]

http://www.thenakedscientists.com/forum/index.php?topic=13103.0

Glad I could help. I asked this question a while back.

It's soft, squishy bits inside you bouncing.

Anything moving will travel in a straight line unless acted on by a force. If you are in a vehicle going over a hump-back bridge then the force is the upward acceleration of the vehicle. The hard parts of you, such as bone, respond quicker than the squishy bits so there is a lag between your bony bits rising with the vehicle and your squishy bits following suit. As you go over the bump and start to come down the other side, your squishy bits are still trying to go up but your hard bits, and gravity, start to pull them down.

You can think of it as being like a bowl of jelly (jello in the U.S.). The jelly can move inside the bowl in the same way that your squishy bits can move a bit inside your body.

heh - Speaking of jello, I've just had a vision of J-Lo going over a hump-back bridge!   )

Yup, that's DoctorBeaver explaination to me.

[DoctorBeaver]

erm... and just whom have you quoted in your reply without credit?

[lyner]

Hello Emil
Actually, I think it's really all in your head - like when you feel sick in a car or in a boat.
Inside your head (near your ears) are some very sensitive organs which help you to keep your balance. When you fall in a lift or aeroplane, they detect it and you 'feel' it in your stomach. It happens if you jump off a high wall (or, better, of a high diving board) but it's worse in a plane because you aren't expecting it and it lasts for longer.

[Alan McDougall]

Emilie,

It has to do with gravity, when the plane or elevator drops suddenly gravity lessens very slightly and your body which s a marvelous precision machine notices this change and send the single t your brain that you misinterprets as losing your stomach.

This is a good question you know and similar to one Einstein asked himself in one of his famous thought experiment. What would happen to a person in a lift were the rope broke etc.

Alan

[orca]

when accelerating downward, your weight becomes m(g - a), where m is the mass of your body, g is the acceleration due to gravity, and a is your acceleration. So you experience the very uncomfortable weightlessness to some extent.

[Simulated]

erm... and just whom have you quoted in your reply without credit?

Heyy I sent them the link. I sorry Doc. I was wrong for doing that wasn't I.