[devils advocate]

So we are told that UA is equivalent to gravity, by Einstein who certainly had a better grasp of physics than me, however as he's dead can anyone else answer the following please?

To use Tom's example, when we step off a chair the ground rises up to meet us (not we fall down to the ground)

Thus when I jumped out of a plane the sensation and sight I had of me rushing towards the earth was actually earth rushing up to meet me right?!

So how do parachutes works? With gravity It's easy, my pull towards the ground is being countered by the Parachute but how does UA explain my extended time in the air. It can't be that my Chute was actually slowing down the earth's upwards motion can it?

Danke 

[Curious Squirrel]

So we are told that UA is equivalent to gravity, by Einstein who certainly had a better grasp of physics than me, however as he's dead can anyone else answer the following please?

To use Tom's example, when we step off a chair the ground rises up to meet us (not we fall down to the ground)

Thus when I jumped out of a plane the sensation and sight I had of me rushing towards the earth was actually earth rushing up to meet me right?!

So how do parachutes works? With gravity It's easy, my pull towards the ground is being countered by the Parachute but how does UA explain my extended time in the air. It can't be that my Chute was actually slowing down the earth's upwards motion can it?

Danke 

It's all the same forces at work. The reason you fall slower is air resistance in both models. Air resistance works exactly the same for each, working like friction to pull you up/away from the Earth. With gravity it slows your descent. With UA it functions sort of like the ground, accelerating you at a speed less than 9.8 m/s/s because of the reduced resistance relative to the resistance of the ground.

That said, we're not going to disprove UA. We can show there's no evidence preferring UA over anything else relatively easily, but we can't conclusively rule out UA with simple tests or exercises like this.

[devils advocate]

Cheers for that, am I right then in saying that UA is kind of "pushing" the air up in front of it and as this air hits my Chute that friction is the cause of earth not rushing to meet me as quickly as without the chute? In effect I am being slightly propelled upwards by the up-draft?

[Curious Squirrel]

Cheers for that, am I right then in saying that UA is kind of "pushing" the air up in front of it and as this air hits my Chute that friction is the cause of earth not rushing to meet me as quickly as without the chute? In effect I am being slightly propelled upwards by the up-draft?

That's a good way to look at it indeed!

[devils advocate]

Cool well cheers for that CS, I can get my head round this idea a bit now. 

DA

[douglips]

There are places you can go and pay money to “skydive” indoors. Upward rushing air pushes on you or a parachute exactly the same whether it’s gravity or UA doing the work.

[Tom Haws]

I am a civil engineer. And I endorse this message. The primary distinction between UA and gravity is that UA cannot "attract" people to the "bottom" of the earth. Rather, it would "repel" them. Does not work, in other words, for, say, hmm, a Round Earth.