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That tower question (1 Viewer)

Sindivyn

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Did people put the object dropped from the tower at the equator will orbit the earth, and stay motionless relative to the tower? I've spoken to 30ish people about it, everyone had something different :(
 

EinstenICEBERG

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for me.. Tower A dropped faster than tower B as the pole is closer to the center of the Earth thus higher g value. Also at tower A, the orbital motion of Earth, makes it drop down in a parabolic motion like Newton's thought experiment, and in tower A it is in earth's rotational motion, thus is will head towards the easterly direction. hopes that right ^^
 

cartoonmaiz

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I talked about the variation in the acceleration due to gravity and lightly touched on the vertical and horizontal motions being independent...
 

machine2035

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I said orbit, but to tell you the truth I had NFI and just wrote total baloney.
 

nucgaek

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Pretty sure it was

Tower A: It fell right onto the north pole

Tower B: It stayed at the point of release, acting as a geostationary satellite would.

Explain a bit on why Tower A is not geostationary... should be 4. Too bad I'll be lucky to get one :O
 

Demise

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I talked about both the change in the Earths gravitational at different places, but the question also specifically said at identical heights (geostationary), so I said consistent acceleration saying that they'll both fall at the same rate of 9.8ms-2 and would reach the earth at the same time.
 

Demise

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Pretty sure it was

Tower A: It fell right onto the north pole

Tower B: It stayed at the point of release, acting as a geostationary satellite would.

Explain a bit on why Tower A is not geostationary... should be 4. Too bad I'll be lucky to get one :O
Both where at Geostationary points. If one stayed up, so would the other one.
 

Sindivyn

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Pretty sure it was

Tower A: It fell right onto the north pole

Tower B: It stayed at the point of release, acting as a geostationary satellite would.

Explain a bit on why Tower A is not geostationary... should be 4. Too bad I'll be lucky to get one :O
Yeah, that's pretty much what I had, since it would be released at the same velocity of a geostationary satellite.
 

Sindivyn

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Both where at Geostationary points. If one stayed up, so would the other one.
The mass on the tower on the equator would have a higher velocity than earth's rotation, allowing it to stay up and orbit. The mass on the tower of the north pole has no velocity relative to earth though
 

Kimyia

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Bahaha had no idea so just wrote BS for most of it
 

nucgaek

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The mass on the tower on the equator would have a higher velocity than earth's rotation, allowing it to stay up and orbit. The mass on the tower of the north pole has no velocity relative to earth though
It's exactly why all geostationary satellites must be above the equator... At the north pole there's nothing keeping them up there.
 

chriss95

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but if you drop it straight down shouldn't it just fall straight down? I don't understand how it could stay in orbit. He's not projecting it horizontally.
 

Sindivyn

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but if you drop it straight down shouldn't it just fall straight down? I don't understand how it could stay in orbit. He's not projecting it horizontally.
The earth spins at a (fairly) constant rate, the further away an attached object is from earth, the faster it moves. Therefore, it has a velocity relative to earth, allowing it to enter orbit through centripetal force.

That's my understanding anyway
 

nucgaek

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but if you drop it straight down shouldn't it just fall straight down? I don't understand how it could stay in orbit. He's not projecting it horizontally.
For tower B, it is undergoing orbital velocity due to the spin of earth on its axis
 

clarg

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but if you drop it straight down shouldn't it just fall straight down? I don't understand how it could stay in orbit. He's not projecting it horizontally.
The rotational velocity keeps it in a orbit lower than Geostationary - at least thats what I said for tower B.
 

LifeBoats

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I talked about both the change in the Earths gravitational at different places, but the question also specifically said at identical heights (geostationary), so I said consistent acceleration saying that they'll both fall at the same rate of 9.8ms-2 and would reach the earth at the same time.
This, indeed!
 

Automatia

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Unless the tower was like 35800km high, the object would fall down, except a bit to the left of the tower due to the rotation of the earth. It does NOT keep it geostationary.
Well the tower was that high because the question said that the towers were as high as a geostationary orbit. The mass at the pole has no velocity and so falls down to earth. The mass at the equator has a 24 hour period because of earths rotation speed and so had the velocity required for a geostationary orbit.
 

iampeterr

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i talked about how earth isn't a perfect sphere, so the gravitational acceleration is different around the earth. tower A would of reached the surface first .. i think.
 

nucgaek

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Unless the tower was like 35800km high, the object would fall down, except a bit to the left of the tower due to the rotation of the earth. It does NOT keep it geostationary.
the question said "at the height of a geostationary sattelite"... isn't that 35800km?
 

barbernator

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Well the tower was that high because the question said that the towers were as high as a geostationary orbit. The mass at the pole has no velocity and so falls down to earth. The mass at the equator has a 24 hour period because of earths rotation speed and so had the velocity required for a geostationary orbit.
lol shit
 

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