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Answer me this...


Hills Bro
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If its dark and you are traveling at the speed of light with your headlights on.

You wont see light in front of you because light would have to travel faster than you to reflect back to you.

You wont see light behind you because light would have to travel faster than you to catch up to you.

Edited by Brother Speed
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Darn friction! Or lack therof..

Yeah, we studied those stinkers in Physics.. frictionless pulleys, frictionless inclines..

Almost like asking which came first, the chicken, or the egg..

No friction, the sucker has to drop like a rock..

I think the answer would be: the vertical and horizontal accelerations would vectorially add up to 9.8 meters per second squared..

But you didn't give us that choice, did you! :lol:

But to be more precise about all of this, have to consider where this miracle device is located.. on the moon, or in orbit, or on the earth..

Whew..

Edited by Mr. Hammeroni
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Yes, it does. But on a frictionless incline, the accelerations would divide in a vectoral manner, with only two directions.. one vertical, one horizontal. Hence, technically, it would not "slide" down the incline.

The manner it divides between the two depends on the angle of the incline. 9.8 times cos of the angle would be the for horizontal acceleration, 9.8 times sin of the angle for vertical acceleration.. if I remember correctly..

Adding them with vector math or trig.. comes up to 9.8

Friction changes EVERYTHING.. heh heh.

I keep editing this sucker.. I think I had it right the first time..

Edited by Mr. Hammeroni
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But.. thinking of Hills' first question..

somehow, the experiment MAY be possible.. but you'd have to go on one of those "wonder" diets.

NO mass, and feasibly, you could travel at the speed of light..

Edited by Mr. Hammeroni
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Y'all didn't scare me! Didn't mean to post & run, but I am actually trying to get some work done and to make my point on the lesbian thread without sounding like one of the posters who get my blood pressure to boiling. :P

My physics teacher and I went round and round on the friction question for a while. Each week we had a different answer and a very plausible reason for said answer. I'm having fun watching your brains in gear, though. :D I think I'll give you a little bit longer to ponder it before I tell you what we finally came up with. Mind you, it may or may not be correct, but it's what we determined.....based, Ham, on the plane & the ball being in Earth's atmosphere and therefore subject to gravity. ;)

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Well, I would think..

NO friction, the ball will NOT rotate.

As the ball moves down the incline, there is a "normal" force exerted on the ball.. equal to mgCos(theta). But with a coefficient of friction being zero.. none of this force would be transferred into the ball.. and since the ball has rotational inertia.. without an external force applied, it will tend to stay in its non-rotating condition.

But add friction.. things are entirely different. Could figure out if the ball actually slides on the incline.. or slips, if you will.

Add the SLIGHTEST amount of friction, and it will rotate.

Now Belle dear, we wait!

And yes Regis, that is my final answer! (for now..)

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If you add atmosphere into the equation the ball rolls because atmosphere creates friction. Without friction, the ball would slide. If you attach a hose to the exhaust of a vacuum cleanerr so that air blows out of the hose, then place a ping pong ball in the air stream, the ball will stay in the air stream bouncing and rotating.

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No, the acceleration due to gravity is STILL 9.8 meters per second.. air or not. The other opposite force of course is acting on the ball.. due to friction.

Two forces. Net acceleration.. of course.. would NOT be 9.8..

OK, you wonderful rascal.. I see you lurking there, laughing at us..

Who gets the million bucks??

Drat.. scared her off..

Now you're back again.. Belle, did anybody ever tell you that you have some of the characteristics of a Cheshire cat? :D

Edited by Mr. Hammeroni
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Y'all are both right! :D

In a TRUE frictionless system we decided that the ball would slide, BUT it would depend on any inertia put on the ball to roll when it was first "set" into motion.

There are really so many variables that can affect the answer. In the Earth's atmosphere and in a non-sterile, truly scientific setting, the ball would roll, as Brother Speed pointed out, because there is friction created naturally. In a sterile, scientifically controlled setting, the ball should slide.

Most scientific experiments used to validate Galileo's formulas and theories are used with a disc instead of a ball because it doesn't roll. :)

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Aww, drats.. now I have to split the million bucks.. :D

Amazing how complex such a little thing can be..

Angular momentum doesn't exactly mess stuff up.. just makes it quite a bit more complex.

Edited by Mr. Hammeroni
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