Why people float inside free falling airplane

[jerromyjon]

can freefall be made to continue forever in park rides

Only simulated by reducing gravity briefly. Most of rollercoaster rides are flipping, rocking, twisting, etc. of drawn out redirected use of gravity for propulsion.

 

[DaveC426913]

will it be possible to create 0g condition on Earth (lasting forever)
a "smaller" giant wheel whose axis is rotated by another "larger" giant wheel.
by varying angular velocity of the two such that vertical projection of resultant acceleration of the seat is always 1g down

Set up a giant free fall elevator.

Free-fall calculator

A 500m elevator with a contained falling capsule would give you a mere 10s of zero-G, not including the deceleration.
You'd need another 90m to declerate at 2(+1)gs in 3.5 seconds.

If you wanted 30s of free-fall, the elevator would have to fall about 4.4km and you'd be doing over 1000km/h.
You'd need to endure 3gs for an additional 10s to decelerate to 0 over 1.4km.

No that would suck.

 

[A.T.]

can freefall be made to continue forever in park rides

Would NASA waste money on jet fuel, if that was possible?

 

[jerromyjon]

can freefall be made to continue forever in park rides

Actually there is another way... imagine you were launched into a hollow cavity in the center of a large solid body out in space in microgravity. You could oscillate through the center for quite some time. Oh, wow, that's the piece I've looking for, for something different entirely!

 

[DaveC426913]

Actually there is another way... imagine you were launched into a hollow cavity in the center of a large solid body out in space in microgravity. You could oscillate through the center for quite some time. Oh, wow, that's the piece I've looking for, for something different entirely!

If you were in orbit then you would certainly be in microgravity, yes.

But you'd need 20 million 'good for one ride' coupons. And the lineup wait time would out Disneyworld to shame.

 

[hackhard]

suppose a train travels along equator at 15,600 mph in direction of rotation of Earth gforce on man inside train is 0.
2.5 times speed of rocket sled
https://en.wikipedia.org/wiki/Rocket_sled
20 times speed of hyperloop pod
https://en.wikipedia.org/wiki/Hyperloop

 

[A.T.]

suppose a train travels along equator at 15,600 mph in direction of rotation of Earth gforce on man inside train is 0.

Going into low orbit is simpler.

 

[georgir]

Going into low orbit is simpler.

It actually seems to be the same thing by definition...
Meaning simply that hackhard's train would need no rails aside from the part where it's picking up its speed initially. After that, it is technically in (very) low orbit.
[edit: in practice a way to remove atmospheric drag would be required, which still means probably a vacuum guide tunnel and the maglev equivalent of rails.]
[edit 2: which is probably more complicated than going into a not-so-low low orbit, which finally makes me appreciate the point you were probably making :p]