Which falls faster a Feather or a Bowling Ball

caryc said:

So why did he not burn up when he entered the earth's atmosphere?

Yeah, I'm a dummy. Well, I guess he was still inside the earths gravity pull.

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1G acceleration = 32ft/sec/sec until terminal velocity is reached, which is dependent on the density of the atmosphere at a given altitude. A meteor (or a piece orbiting junk) has a lot of time to accelerate, and typically reaches approx, 45,000 mph(for a meteor), by the time it enters the upper atmosphere at approx. 60-100 miles above sea level and begins frictional heating.

Earth gravity is what keeps the moon, and every earth orbiting satellite in orbit.

caryc said:

So why did he not burn up when he entered the earth's atmosphere?

Yeah, I'm a dummy.

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GunnyGene said:

1G acceleration = 32ft/sec/sec until terminal velocity is reached, which is dependent on the density of the atmosphere at a given altitude. A meteor (or a piece orbiting junk) has a lot of time to accelerate, and typically reaches approx, 45,000 mph(for a meteor), by the time it enters the upper atmosphere at approx. 60-100 miles above sea level and begins frictional heating.

Earth gravity is what keeps the moon, and every earth orbiting satellite in orbit.

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Gunny, you seem to be well versed on this so tell me, what exactly is gravity? Why does it work like it does?

Time creates gravity... True statement.

caryc said:

Gunny, you seem to be well versed on this so tell me, what exactly is gravity? Why does it work like it does?

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You too can be well versed.

Gravity is curved space.

Ride1949 said:

You too can be well versed.

gravity at DuckDuckGo

DuckDuckGo. Privacy, Simplified.

duckduckgo.com

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Nobody really knows what gravity is. All we know are (some) of it's effects. The big brains at CERN are trying to figure out what it actually is.

Click the link, and search for gravity. Learn all about quarks, strings, dark energy, dark matter, anti-matter, and more.

So much for the well versed theory.

GunnyGene said:

Nobody really knows what gravity is. All we know are (some) it's effects. The big brains at CERN are trying to figure out what it actually is.

Click the link, and search for gravity. Learn all about quarks, strings, dark energy, dark matter, anti-matter, and more.

Home | CERN

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works.

home.cern

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Well I don't know about that. If you were a pilot you would understand gravity as I do.
Let me splane this gravity thing so you can understand. We pilots know that the higher you go the more gravity there is and it is trying to smash you into the ground. Which is not good. So what I do is try and fly around an altitude of 500'-- to a MAX of 1500' any higher and the gravity will smash you. Now you pobable ask how those big people hauling airlines can fly so high. That is why they have to have those jet engine things to overcome the gravity.
Well now you know the truth. Just remember the higher you go the more there is.
Glad I could help.

Wyandot Jim said:

Well I don't know about that. If you were a pilot you would understand gravity as I do.
Let me splane this gravity thing so you can understand. We pilots know that the higher you go the more gravity there is and it is trying to smash you into the ground. Which is not good. So what I do is try and fly around an altitude of 500'-- to a MAX of 1500' any higher and the gravity will smash you. Now you pobable ask how those big people hauling airlines can fly so high. That is why they have to have those jet engine things to overcome the gravity.
Well now you know the truth. Just remember the higher you go the more there is.
Glad I could help.

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It's not the fall that kills you. It's the sudden stop when you hit the ground.

Wyandot Jim said:

Well I don't know about that. If you were a pilot you would understand gravity as I do.
Let me splane this gravity thing so you can understand. We pilots know that the higher you go the more gravity there is and it is trying to smash you into the ground. Which is not good. So what I do is try and fly around an altitude of 500'-- to a MAX of 1500' any higher and the gravity will smash you. Now you pobable ask how those big people hauling airlines can fly so high. That is why they have to have those jet engine things to overcome the gravity.
Well now you know the truth. Just remember the higher you go the more there is.
Glad I could help.

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Thanks for that splanation. But since I'm not a pilot and don't play one on TV I guess I don't have to worry too much about it.

caryc said:

Thanks for that splanation. But since I'm not a pilot and don't play one on TV I guess I don't have to worry too much about.

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Well just be careful going up any of those tall mountains you have around you.
Get to high and that gravity will smash you flat

vito said:

Even in an infinite vacuum, neither object would get faster than terminal velocity. This is why sky divers, not matter how high they start from, do not travel at faster than about 125 mph once they reach that speed.

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No in an infinite vacuum, objects would continually accelerate. Here on Earth everything accelerates at 32 feet per second squared. That means every second a falling object falls 32 feet per second faster than the second before. (After one second objects fall at 32 feet/sec. After 2 seconds objects fall at 64 feet/sec, etc)
But this does not take into account the air resistance. Air resistance is what causes the terminal velocity. Something with more air resistance (such as a feather or a parachute) has a slow terminal velocity and falls slowly. Something with low air resistance such as a solid lead bomb with fins will have a much higher terminal velocity.

At the terminal velocity, the air resistance equals the weight of the falling object. (Every action has an equal and opposite reaction)
When a 100 pound object reaches it's terminal velocity there is 100 pounds of air resistance pushing up (resisting any more acceleration). This is just enough to counteract the 100 pounds of downward force due to the object's weight.

When a skydiver reaches his terminal velocity he can go faster by pointing his body down the direction he is going (like Superman). By becoming more streamlined he has reached an new, faster terminal velocity.

Dave P. said:

The physics get iffy at light speed.

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True. In a spaceship trying to go the speed of light, the dimensions of space and time are warped or altered and mass also increases. For example the length of the spaceship would decrease and time would slow down. So if a spaceship were ever able to reach the speed of light it's size would become zero, it's mass would become infinite and time would no longer exist on the spaceship. Since these three conditions are impossible, the speed of light can never be reached.

Wyandot Jim said:

Well I don't know about that. If you were a pilot you would understand gravity as I do.
Let me splane this gravity thing so you can understand. We pilots know that the higher you go the more gravity there is and it is trying to smash you into the ground. Which is not good. So what I do is try and fly around an altitude of 500'-- to a MAX of 1500' any higher and the gravity will smash you. Now you pobable ask how those big people hauling airlines can fly so high. That is why they have to have those jet engine things to overcome the gravity.
Well now you know the truth. Just remember the higher you go the more there is.
Glad I could help.

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Well.... as you go higher, the acceleration due to gravity decreases rather than increases. Acceleration due to gravity varies inversely with the square of the distance between the two objects' center of mass. On earth's surface gravity is about 32 ft/s/s. At the altitude of the ISS, gravity is about 28.5 ft/s/s (assuming an altitude of 250 mi). So... the higher you go, the less gravity there is.

Let's say we're in a spaceship trying to go the speed of light. We calculate that we are going just 10,000 mph slower than the speed of light. We have an extremely high speed gun (Hypothetically faster than current guns) that shoots a particle toward the front of the spaceship.

That particle goes by 2 sensors that are 10 feet apart. We calculate that the particle is going 20,000 mph.

You say "Ha! that particle must have gone faster than the speed of light."
Then you grab a base ball and throw that toward the front of the spaceship and say "Ha! you said things going almost the speed of light would have extremely high mass and feel heavy. I threw that ball as easily as when I was on Earth."

Then I would say "Einstein said motion is relative. Our gun and test equipment are on our spaceship and not moving relative to us."

If our spaceship were to go past a planet. And even more hypothetical, lets say people on that planet could see our test equipment as we flew by. They would say those sensors are not 10 feet apart. They are almost touching each other. And your clock is going extremely slow. It seems to take an eternity before your clock clicks off one millisecond.

In other words your particle is not being shot at 20,000 mph. It's actually taking months (not milliseconds) to go a fraction of an inch (not 10 feet).

Einstein says gravity and inertia are one and the same.

Let's say we are sitting in my Dodge Challenger SRT Demond 170 (hypothetical). I hit the gas and take off. You say the inertia is why we're plastered against the back of our seats.

Then we see a "bridge out ahead" sign and I slam on the brakes. You say our inertia is the reason we are thrown forward as our seat belts strain to hold us in our seat.

Einstein points out that there are an unfathomable amount of stars and galaxies behind us. All this matter has a very strong gravitational pull pulling us backward. Why don't we fall backward? Because there is just as many stars and galaxies in front of us. It's this gravitational pull in all directions that keep us at rest unless a force is applied to move us.

When I hit the gas on my Challenger and accelerate it's the gravitational pull of all the stars and galaxies behind that are pulling us back.

When I hit the brakes it's the gravitational pull of off the stars and galaxies in front of us that are pulling us forward.

Today's lesson boys and girls is there is always gravity pulling on us. We just never notice it until we apply a force to counteract gravity.
For example when we stand on earth our legs are counteracting the gravity of earth and we are aware of Earth's gravity.
You jump off a building you don't notice earth's gravity until you hit the sidewalk.
An astronaut is in orbit around earth. You say there's no gravity when you see the astronaut float in his spaceship. Of course there's gravity. That's what keeps the spaceship in orbit going around and around the earth.
There's always gravity but you never notice it unless you are applying a force to counteract it.

Dave P. said:

Oh you'll notice it all right as the acceleration begins effecting your mass

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Oh yes, correct. Gravity is the reason for your acceleration. And when jumping off a building that acceleration (movement) will be all the more obvious.

When in free fall you don't notice gravity. My example isn't good because visual evidence is obvious. They train astronauts for zero gravity by doing the same thing except in an airplane. They fly high and then start a free fall. If the plane isn't providing any lift people inside don't realize there is any gravity. That would have been a much better example. There you don't see that you are quickly approaching the ground as when jumping off a building.

An astronaut orbiting earth may think he's far from any gravitational field. Then he looks out the window and sees earth. In an hour and a half he'll orbit the earth. The gravity is the reason for his path.

In the plane an astronaut trainee may also think he's far from any gravitational field until he looks out the window. But gravity is the reason for the planes free fall path.

Jumping off a building it's much more obvious that gravity is the reason your quickly approaching the ground. That's why my example was a poor one.

Durango Dave said:

Oh yes, correct. Gravity is the reason for your acceleration. And when jumping off a building that acceleration (movement) will be all the more obvious.

When in free fall you don't notice gravity. My example isn't good because visual evidence is obvious. They train astronauts for zero gravity by doing the same thing except in an airplane. They fly high and then start a free fall. If the plane isn't providing any lift people inside don't realize there is any gravity. That would have been a much better example. There you don't see that you are quickly approaching the ground as when jumping off a building.

An astronaut orbiting earth may think he's far from any gravitational field. Then he looks out the window and sees earth. In an hour and a half he'll orbit the earth. The gravity is the reason for his path.

In the plane an astronaut trainee may also think he's far from any gravitational field until he looks out the window. But gravity is the reason for the planes free fall path.

Jumping off a building it's much more obvious that gravity is the reason your quickly approaching the ground. That's why my example was a poor one.

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When this plane is in free fall your body definitely knew it free falling and was experiencing zero G. That much we both agree on. But what I'm saying is when the plane is in free fall it is exactly the same as if the plane was far out in space, far from Earth, any other planet, star or any other gravitational force. It's the same as if there is no gravity.

When the pilot pulls up to suddenly level out after the zero G free fall, everyone in the plane experiences 1.8 G force down. This is exactly the same as if they were on a planet much larger than earth that had a gravity of 1.8 times that of earth.

When a pilot experiences G forces due to airplane maneuvers we say that's inertia (your body wants to keep moving in a strait line).
When you are on a large planet and experience 1.8 times the force of standing on Earth, we say that's gravity.
Einstein says inertia and gravity are one and the same. They are the same force.

Durango Dave said:

When this plane is in free fall your body definitely knew it free falling and was experiencing zero G. That much we both agree on. But what I'm saying is when the plane is in free fall it is exactly the same as if the plane was far out in space, far from Earth, any other planet, star or any other gravitational force. It's the same as if there is no gravity.

When the pilot pulls up to suddenly level out after the zero G free fall, everyone in the plane experiences 1.8 G force down. This is exactly the same as if they were on a planet much larger than earth that had a gravity of 1.8 times that of earth.

When a pilot experiences G forces due to airplane maneuvers we say that's inertia (your body wants to keep moving in a strait line).
When you are on a large planet and experience 1.8 times the force of standing on Earth, we say that's gravity.
Einstein says inertia and gravity are one and the same. They are the same force.

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Isn't it safe to say that the lady above is just falling with the plane?