there is no ball
Printable View
there is no ball
[QUOTE=GregariousWolf;1258356471]Constant velocity upward means zero upward acceleration. The only acceleration the ball experiences is 9.8m/s down due to gravity. As soon as it rolls out of the basket, the ball will fall.[/QUOTE]
Except that it has an upwards velocity because the balloon is going up. Therefore it'll take some time (velocity/9.81 to be exact) before the velocity of the ball reaches zero and the ball will start falling down.
[QUOTE=neighborr;1258359741]Interesting replies thus far but no general consensus...[/QUOTE]
No general consensus because you gave no frame of reference. Obviously there are gonna be different answers because people are using different frames of reference.
[QUOTE=UofACATS;1258359561]You mean the energy it has because it's in motion? You hold a ball over the side of a balloon, that ball is motionless with you as the reference point because you're holding it.
Drop the ball. You think the ball actually goes up into your hand before it goes down?
Not even once.[/QUOTE]
For me: frame of reference = earth.
If your frame of reference is the balloon, then the ball has no kinetic energy.
[QUOTE=ImHuge07;1258337921]The airplane doesn't take off[/QUOTE]
I think I'm aware but not sure
Say the balloon goes up at v metres/second, relative to the earth. When you release the ball it will travel upwards, but while accelerating downwards, after (v/9.81)seconds it will stop travelling up, be momentarily at rest, then fall to earth.
[QUOTE=auroturtle;1258344331]lmfao so many physics terms and not one was used correctly
am i missing the joke?
this[/QUOTE]
Nah sounds like you got the joke brah
Edit: What I said is same as below post'
Extreme example, if you stuck your hand out of a rocket and let go of a tennis ball, it's not just going to lose suddenly the momentum it had and drop straight away. Similarly, if you hold a ball out and jump, if you let go as you're travelling upwards, the ball will continue to travel upwards until gravity brings it down
[QUOTE=shtabe;1258346841]up you freaks. its speed/direction is relative to the ballon. the same moment you let it go it's going up for a fraction of a second til gravity kicks in[/QUOTE]
Gravity kicks in immediately... always.. it's not like the ball will do something then gravity turns on.
delta_x = v0 * t + 0.5 * a * t^2
up is positive, down is negative
v0 is positive, t is 0.00000 (infinite) 00000 1
a is negative 9.81 m/s ^2
So the TRUE answer is it depends on the velocity of the balloon going up.
[QUOTE=Nitsua24;1258362031]I think I'm aware but not sure[/QUOTE]
guaranteed argument starter..
Never took physics so i got no clues
[QUOTE=UofACATS;1258359561]You mean the energy it has because it's in motion? You hold a ball over the side of a balloon, that ball is motionless with you as the reference point because you're holding it.
Drop the ball. You think the ball actually goes up into your hand before it goes down?
Not even once.[/QUOTE]
Your hand is also going up because you're in the balloon.
[QUOTE=plsbenotsrs;1258354421]But who was kinetic energy that just disappears according to your answer?[/QUOTE]
haha
it will travel upwards ever so slightly due to it being already in motion traveling upwards in the balloo, as soon as you release the ball over the side with no downward force it will move slightly up, then fall to earth
[QUOTE=JDawn99;1258362851]Gravity kicks in immediately... always.. it's not like the ball will do something then gravity turns on.
delta_x = v0 * t + 0.5 * a * t^2
up is positive, down is negative
v0 is positive, t is 0.00000 (infinite) 00000 1
a is negative 9.81 m/s ^2
So the TRUE answer is it depends on the velocity of the balloon going up.[/QUOTE]
No. Draw the funcion you just wrote down. However small the starting speed, there will always be a period of time, when v0*t > 0.5a * t^2
Can a fly stop a train? Yep. When a train hits a fly, the fly goes from 1MPH forwards to 60 MPH backwards, at some point though, the fly is at 0 MPH, if the fly is at 0 MPH then the train is too.
An object in motion tends to stay in motion unless acted upon by an outside force. If you push a marble across the floor does the marble stop immediately when you stop pushing it?
Throw a ball in the air. The moment it leaves your hand, is it going up, or down?
ITT: UXDork schools everyone and wins the thread.
[QUOTE=GregariousWolf;1258356471]Constant velocity upward means zero upward acceleration. The only acceleration the ball experiences is 9.8m/s down due to gravity. As soon as it rolls out of the basket, the ball will fall.[/QUOTE]
Relative to earth, the ball is traveling upward at the same velocity that the balloon is rising. Keep in mind that velocity is a vector, not a scalar. Let us say that it has a positive velocity. Once the ball is released, it must first decelerate to zero velocity (courtesy of the -9.8m/s^2 acceleration imparted by earth) before gaining a negative velocity.
Example:
We are going up at 19.6m/s. So then, is the ball. If you use the formula [ acceleration = change in velocity / change in time ], you can determine with substitution that the acceleration due to earth will take 2 seconds (at -9.8m/s^2) to bring the ball to a 0 velocity. During that time it will still be traveling (albeit more and more slowly) farther from earth. Then after that instant at the 2-second mark, it will gain a negative velocity and afterward be traveling toward earth or "down".
[QUOTE=plsbenotsrs;1258364511]No. Draw the funcion you just wrote down. However small the starting speed, there will always be a period of time, when v0*t > 0.5a * t^2[/QUOTE]
This, so much retardation in this thread.
[QUOTE=hammerfelt;1258364861]An object in motion tends to stay in motion unless acted upon by an outside force. If you push a marble across the floor does the marble stop immediately when you stop pushing it?[/QUOTE]
If you push bags of sand across the floor do the bags stop immediately when you stop pushing them?
how fast is the fukking balloon ascending?
"If you use the formula..." right, let me just go cut my head off and swap to another one...
it is momentarily at rest *******, as soon as the hand leaves t=0seconds.
[QUOTE=hammerfelt;1258364861]An object in motion tends to stay in motion unless acted upon by an outside force. If you push a marble across the floor does the marble stop immediately when you stop pushing it?[/QUOTE]
There is upward reaction force on the ball from the hand due to gravity. However, it's not being accelerated upward. I need to think about it more but I'm tending say that it will fall down immediately.
edit: i think i may have just gone full potato as the ball needs to change direction.
[QUOTE=JDawn99;1258363371]Your hand is also going up because you're in the balloon.[/QUOTE]
Take a dump on an airplane. The moment the poop leaves the hole, where does it go?
Forward with the plane right.
how can you answer this correctly when hot air balloons arent even real ?
[QUOTE=chino3;1258365511]how fast is the fukking balloon ascending?[/QUOTE]i dont believe that makes a difference brah
It Will go up,down,left,right,square, arrow, circle.
What did I win?
[QUOTE=UofACATS;1258367571]Take a dump on an airplane. The moment the poop leaves the hole, where does it go?
Forward with the plane right.[/QUOTE]
Chill man, you keep takin the moving object as a frame of reference, we keep taking earth.
[QUOTE=DIELBrah69;1258366601]it is momentarily at rest *******, as soon as the hand leaves t=0seconds.[/QUOTE]
momentarily at rest from the perspective of the guy in the balloon. It is going up from the perspective of a guy on the ground, since it is travelling with the balloon's velocity.
[QUOTE=plsbenotsrs;1258368841]you keep takin the moving object as a frame of reference, we keep taking earth.[/QUOTE]
Earth would be the reference point if the original question asked a person standing on the earth what happens to the ball.