Thread: if you trow a beam from a plane does it fall vertical or horizontal?

1. i cant figure it out

2.

3. Depends where its center of gravity is...

4. If you mean a light beam, it goes in whatever direction you point it, subject to refraction by the atmosphere.

5. a beam like this I

so does potential energy tend to spend the faster or the slower?

6. Originally Posted by luxtpm
a beam like this I

so does potential energy tend to spend the faster or the slower?
It's not a question of potential energy. If the beam is uniform, the force of gravity acts on its geometric center. If the opposing aerodynamic force acts at the same point, there will be no torque. If it is off center, there will be a torque.

If the beam is perfectly horizontal, or perfectly vertical, there should not be any difference between the air resistance on one side or the other. If it becomes slightly tilted, I'm not sure exactly what would happen.

7. thake this other problem:

why a beam of density 0.5 floats horizontal if if vertical has identical sunk volume than horizontally

in a way dinamic sustentation is like buoyancy so iwould expect it to fall horizontally

8. Do you want to try to ask those sames questions again?

This time please use English as the chosen language and employ proper grammar and punctuation.

9. John, this a rude, even chauvinistic comment

Not all members here have English as their first language. So what? We welcome members of all nationalities here, even those whose command of English grammar and spelling is not quite to your taste.

I note that my use of "English English" often differs markedly from those who use American English.

Do I complain about this? No. I try to unpick (and forgive) what to my purist ears seems a criminal abuse of language by our US cousins.

So leave off - let luxtpm make his points in peace

10. Yeah sorry for my erngrish

In a way dynamic sustentation is like buoyancy

So the same a beam of density 0.5 which takes the same sink volume either floating horizontal than vertical floats horizontally, I understand a falling beam will prefer to fall horizontal which points that nature having to chose prefers to spend energy slowly, since this way it will fall slower

11. Originally Posted by luxtpm
Yeah sorry for my erngrish

In a way dynamic sustentation is like buoyancy

So the same a beam of density 0.5 which takes the same sink volume either floating horizontal than vertical floats horizontally, I understand a falling beam will prefer to fall horizontal which points that nature having to chose prefers to spend energy slowly, since this way it will fall slower
It's a completely different situation. If the beam is floating on top of the water, then the side that lifts up out of the water loses its buoyancy, and there is a torque which restores it to the horizontal position. This is not the case for an object falling through the air.

12. hum seems you figured it out:

torque will be greater horizontally than vertical

so it should fall vertical

thanks

13. Originally Posted by luxtpm
hum seems you figured it out:

torque will be greater horizontally than vertical

so it should fall vertical

thanks
Why do you think the torque would be greater horizontally?

14. more surface

15. There is no more surface on one side of the center of gravity than on the other side.

16. well actually if the beam has some thickness it does, as soon as it leans a litle to a side it presents more surface from the cog one side than the other, anyway now you made me unsure ill try to make an experiment

edit:

well i did the experiment with a rolling paper and it falls horizontal now i would like to know why

17. Brief series of experiments with a pencil seems to indicate that the orientation of the dropped object does not change unless there is a marked discrepency in air resistence at one end.

18. Originally Posted by Sealeaf
Brief series of experiments with a pencil seems to indicate that the orientation of the dropped object does not change unless there is a marked discrepency in air resistence at one end.
it should reach terminal velocity

a pencil doesnt reach terminal velocity at home but a piece of paper does

19. As the beam will be subject to turbulence when leaving the plane, it will tumble - except if it has a dent or curve or other such thing stabilizing it in one way.

20. Originally Posted by luxtpm
a pencil doesnt reach terminal velocity at home but a piece of paper does
"At home"? You mean if I drop a pencil in the office it will reach terminal velocity, but if I do it in my kitchen, it won't?

21. anyway i figured out by game aviation forums that an uncouncious parachitist falls horizontal

22. Yeah, that's a good source for science. Can we get this out of Physics now?

23. well i was told by witness how uncouncious chutist fall horizontal

 Bookmarks
Bookmarks
 Posting Permissions
 You may not post new threads You may not post replies You may not post attachments You may not edit your posts   BB code is On Smilies are On [IMG] code is On [VIDEO] code is On HTML code is Off Trackbacks are Off Pingbacks are Off Refbacks are On Terms of Use Agreement