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throw it straightup.

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You throw the ball up as hard as you can, ON EARTH, and then you catch it.

This isn't Star Trek.

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uummmm, throw it strait up into the air??? that uh, that uh ever cross anyones mind? no? ok. or, your could play fetch with a dog. its said not with another person. but not a dog! eh? eh? EH!?! yyyeeeeaahhhh

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We were thinking of different answers. Throwing it up in the air was the obvious one.

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We were thinking of different answers. Throwing it up in the air was the obvious one.

i did. i said a dog. it said no one else, but not a dog. or mabye the balls really an armidillo!ad it opens up adn crallls bak to you!

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if you throw the ball straight up in the air you can throw it as hard as you can and it will come back to you without hitting anything

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Why hasn't anybody stated the obvious? Just throw the damm thing straight into the air as hard as you can. Why is it necessary for an angle? hmmmmmmmmmmmm...

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Why not throw it straight up? (or at an appropriate angle to compensate for wind resistance, planetary rotation, etc.)

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Am I not getting this? Throw the ball straight up, it will come back to you! Yes?

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This is not as elegant a solution, but...

If you were on a planet with just the right mass and diameter, you're hardest throw in the right direction would allow the ball to orbit the planet once (or twice, etc. depending on the constants just mentioned).

here's why that's a problem. the earth's diameter is about 7900 miles. when the ball is thrown it will not only be traveling around the world but also falling. what that means is that the ball has to travel 7900 miles before it falls 6 feet. with some physics (or a stop watch) we find that an object falls to the earth from 6 feet in about 0.61 seconds. convert 7900 miles per 0.61 seconds to mph and you get 46,622,951 mph!! earth's escape velocity is 25000 mph. so once you threw the ball at 47,000,000 mph it would just keep going out into space instead of curving around the earth.

sorry

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This is not as elegant a solution, but...

If you were on a planet with just the right mass and diameter, you're hardest throw in the right direction would allow the ball to orbit the planet once (or twice, etc. depending on the constants just mentioned).

here's why that's a problem. the earth's diameter is about 7900 miles. when the ball is thrown it will not only be traveling around the world but also falling. what that means is that the ball has to travel 7900 miles before it falls 6 feet. with some physics (or a stop watch) we find that an object falls to the earth from 6 feet in about 0.61 seconds. convert 7900 miles per 0.61 seconds to mph and you get 46,622,951 mph!! earth's escape velocity is 25000 mph. so once you threw the ball at 47,000,000 mph it would just keep going out into space instead of curving around the earth.

sorry

ok, i realize you said if you were on the right planet with just the right mass and diameter and you're right about that (i kind of want to calculate this one for the moon now) but i wanted to at least show people why that solution wouldn't work here on our home planet

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This is not as elegant a solution, but...

If you were on a planet with just the right mass and diameter, you're hardest throw in the right direction would allow the ball to orbit the planet once (or twice, etc. depending on the constants just mentioned).

here's why that's a problem. the earth's diameter is about 7900 miles. when the ball is thrown it will not only be traveling around the world but also falling. what that means is that the ball has to travel 7900 miles before it falls 6 feet. with some physics (or a stop watch) we find that an object falls to the earth from 6 feet in about 0.61 seconds. convert 7900 miles per 0.61 seconds to mph and you get 46,622,951 mph!! earth's escape velocity is 25000 mph. so once you threw the ball at 47,000,000 mph it would just keep going out into space instead of curving around the earth.

sorry

AAARRRGGGHHHH!!!! I just realized I used the diameter when I should have been looking at the circumference. Here it is again, revised

earth's diameter: 24900 miles

drop height: 6 ft

drop time: 0.61 seconds

necessary object speed: 146,950,819.7 mph

ha! you'd have to throw it pi times faster than i erroneously calculated. good luck with that

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and as a final FYI.

On the moon.

escape velocity: 5300 mph

gravity: 5.33 ft/s^2

drop time: 1.061 seconds

necessary object speed: 23,038,821 mph

Given all earth conditions are the same except for the earth's circumference

the circumference would have to be: no more than 4.2 miles

the object's thrown speed would have to be: 24767.89 mph

which would mean it's density would be: as best as i can calculate-about 10^1013 lb/ft^3

which means that earth would basically be close to a black hole. and, of course, if the density were this great then the gravity would change and you'd have to recalculate it again.

another interesting way to look at it that i just thought of is to compare the object speeds to the speed of light. taking earth as it is, i found earlier that the ball would have to be thrown at about 147,000,000 mph

speed of light: 670,600,000 mph

so about 1/5 the speed of light

again, good luck with that

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Einsteins theorised (and later proved) effects would start to be noticable on the ball. In the observer's frame of reference: the ball would look squished horizontally (the direction it was moving), its mass would increase and less time would appear to pass on it.

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you would throw the ball streight above your head and then it will come back to you.

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ok, yall are making this problem way too complicated...just throw the ball up...straight up...gravity will take effect and the ball will fall back down to you...

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yeah, people. this is supposed to be a simple riddle with a catch. there should be no more discussion after we know the catch. jeez.

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You throw it upwards. what comes up will come down

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throw it straight up, drrr

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Hi all this is my first post here...

K, so here it is.

First of all, @all (people looking for a solution), throw the ball up.

Second, @all (music lovers) throw the ball "around" anything coz Sir Justin Timberlake says that "What Goes Around... Comes back Around".

@all (physics "studs"), if you "think" then please think...

There is a particular velocity you can give to the ball with which it will rotate around "Earth" (and you know this ain't a forum for Martians even at the height of 6 ft.

This speed is (gR)^0.5. Where, g is gravitational acceleration and R is radius of earth + 6 ft (or whatever your height is). Which for Earth is 7920 m/s. And yeah Martians, you too can use this formula and you won't encounter any problems coz you are using "Universal Translator".

A big ROFLMAO to all those who didn't figure out this.

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Because...

F = GMm/Â®^2

also,

F = m(v)^2/R

equating and using, g = GM/Â®^2

you get,

v = (gR)^0.5

And now, for god's sake please look for easy solutions, because...

We were already stupid enough to develop "Zero Gravity Ballpens" consuming so much time and resources when we could have used pencils.

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Throw the ball vertically upwards

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what the sh** you guys talking about.... well aside rookiedudester... dont be such a nerdies.......

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If your on earth, with normal earthly powers, just throw the ball vertically up as hard as you can. It is likely that it won't escape the earth's orbit, and as the sond says, "what goes up... must come down". So, catch it.

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throw it upwards into the air

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