Science Something amazing to tell you concerning physics and motion

Jenson71 · 06-04-2009, 10:15 AM

This blows my mind.

Okay, say you have two ball bearings. You hold one in your hand and drop it. The other you put in a gun, point it straight forward, as level as the one in your hand, and pull the trigger, sending it hundreds of yards.

Which one lands first?

The one dropped in your hand right? RIGHT!?!?

No, actually they both hit the ground at the same time.

This is because the vertical component of motion is the same for both objects. They both fall vertically the same distance at about 10 meters per second squared (gravity, actually more like 9.8).

But Jenson, Jenson! What about the horizontal component of the gun-fired ball bearing? Actually, when air resistance is small enough to ignore as it is in this case (being that the bearings are exactly alike), the horizontal and vertical components of a projectile's velocity are completely independent of one another.

And, in this experiment, the gun-fired bearing is constantly falling from the moment it is fired. Yes, it looks like it is holding up in a straight line, but, it's actually falling and it's just hard to see with our eyes. And again, it is falling at exactly the same speed as the ball bearing you released in your hand -- the speed of gravity.

Post more cool science things in this thread.

I think I will later post Aristotle vs. Galileo and gravity, for a little history spin on science.

Mr. Plow · 06-04-2009, 10:17 AM

Don't spit into the wind.

Chiefs=Champions · 06-04-2009, 10:20 AM

Neeeeeeeeeeeeeeeeeeerrrrrrrrrrrrrrrd!!!

Thats pretty interesting though...

**Buehler445** · 06-04-2009, 10:21 AM

You didn't know that? I learned that shit in my HS physics class. -9.8 m/s2 is stuck in my head for eternity.

WTF are they teaching you?
Posted via Mobile Device

Jenson71 · 06-04-2009, 10:23 AM

Quote:

Originally Posted by Buehler445

You didn't know that? I learned that shit in my HS physics class. -9.8 m/s2 is stuck in my head for eternity.

WTF are they teaching you?

Everything I was taught in high school physics I also forgot the very same day. I was a horrible, horrible high school student and I feel bad about it these days.

EyePod · 06-04-2009, 10:45 AM

Quote:

Originally Posted by Buehler445

You didn't know that? I learned that shit in my HS physics class. -9.8 m/s2 is stuck in my head for eternity.

WTF are they teaching you?
Posted via Mobile Device

I got accepted to college, then read the entire hitch hiker's guide to the galaxy series (i have a book that looks like a bible that contains all of the stories) instead of paying attention senior year in physics. Then I went to school for engineering, and I had to learn all the stuff that I should have learned in senior year during my freshman college year again. I was pissed that I didn't just pay attention during senior year of HS...

damaticous · 06-04-2009, 10:22 AM

Actually, from what I remember, the ball bearing in your hand would hit the ground first.

when you fire a bullet from a gun the bullet tends to arch upward a bit, so it is actually falling at a different height from the one that is dropped.

I could be wrong, but I remember reading that or seeing it on TV or something.

Otherwise, yes, they'd hit the ground at the same time.

Jenson71 · 06-04-2009, 10:24 AM

Quote:

Originally Posted by damaticous

Actually, from what I remember, the ball bearing in your hand would hit the ground first.

when you fire a bullet from a gun the bullet tends to arch upward a bit, so it is actually falling at a different height from the one that is dropped.

I could be wrong, but I remember reading that or seeing it on TV or something.

Otherwise, yes, they'd hit the ground at the same time.

Oh, ah... we're discussing a perfect gun that does not send a bullet upward at all.

But yeah, that would screw it up.

damaticous · 06-04-2009, 10:25 AM

Quote:

Originally Posted by Jenson71

Oh, ah... we're discussing a perfect gun that does not send a bullet upward at all.

But yeah, that would screw it up.

O I C

Pitt Gorilla · 06-04-2009, 09:13 PM

Physics 101. Good stuff.

headsnap · 06-04-2009, 09:14 PM

Quote:

Originally Posted by Pitt Gorilla

Physics 101. Good stuff.

it's almost as bad as Econ 101 over in DC...

**notorious** · 06-04-2009, 10:28 AM

Quote:

Originally Posted by Jenson71

Oh, ah... we're discussing a perfect gun that does not send a bullet upward at all.

But yeah, that would screw it up.

I thought this at first, but as the bullet spins, it will create pressure differences (high or Low which creates lift) equal to all sides, which will cancel out any lift/gravity change. Only outside forces, such as updrafts and downdrafts will effect it's decent rate.

Jenson71 · 06-04-2009, 10:30 AM

Quote:

Originally Posted by notorious

I thought this at first, but as the bullet spins, it will create pressure differences (high or Low which creates lift) equal to all sides, which will cancel out any lift/gravity change. Only outside forces, such as updrafts and downdrafts will effect it's decent rate.

Oh, and we're in a vacuum.

Radar Chief · 06-04-2009, 10:39 AM

Quote:

Originally Posted by damaticous

Actually, from what I remember, the ball bearing in your hand would hit the ground first.

when you fire a bullet from a gun the bullet tends to arch upward a bit, so it is actually falling at a different height from the one that is dropped.

I could be wrong, but I remember reading that or seeing it on TV or something.

Otherwise, yes, they'd hit the ground at the same time.

Not quite.
A bullet starts to drop the moment it leaves the barrel. Because of that the sites are adjusted so that the barrel is actually aimed higher that what the sites indicate so that the bullet “falls” into the target at the point predicted by the sites.
The sites are also aimed slightly to the right, IIRC, because the bullet comes out spinning and will move slightly from left to right as it travels.

damaticous · 06-04-2009, 10:54 AM

Quote:

Originally Posted by Radar Chief

Not quite.
A bullet starts to drop the moment it leaves the barrel. Because of that the sites are adjusted so that the barrel is actually aimed higher that what the sites indicate so that the bullet “falls” into the target at the point predicted by the sites.
The sites are also aimed slightly to the right, IIRC, because the bullet comes out spinning and will move slightly from left to right as it travels.

Interesting. That makes sense.

06-04-2009, 10:15 AM	Topic Starter
Jenson71 fides quaerens intellectum Join Date: Oct 2003 Location: United States Casino cash: $8330900	Something amazing to tell you concerning physics and motion This blows my mind. Okay, say you have two ball bearings. You hold one in your hand and drop it. The other you put in a gun, point it straight forward, as level as the one in your hand, and pull the trigger, sending it hundreds of yards. Which one lands first? The one dropped in your hand right? RIGHT!?!? No, actually they both hit the ground at the same time. This is because the vertical component of motion is the same for both objects. They both fall vertically the same distance at about 10 meters per second squared (gravity, actually more like 9.8). But Jenson, Jenson! What about the horizontal component of the gun-fired ball bearing? Actually, when air resistance is small enough to ignore as it is in this case (being that the bearings are exactly alike), the horizontal and vertical components of a projectile's velocity are completely independent of one another. And, in this experiment, the gun-fired bearing is constantly falling from the moment it is fired. Yes, it looks like it is holding up in a straight line, but, it's actually falling and it's just hard to see with our eyes. And again, it is falling at exactly the same speed as the ball bearing you released in your hand -- the speed of gravity. Post more cool science things in this thread. I think I will later post Aristotle vs. Galileo and gravity, for a little history spin on science.
Posts: 15,986

06-04-2009, 10:17 AM	#2
Mr. Plow In Search of a Life Join Date: Dec 2005 Casino cash: $-1342609	Don't spit into the wind.
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06-04-2009, 10:20 AM	#3
Chiefs=Champions Training Camp Hero Join Date: Oct 2006 Casino cash: $8044801	Neeeeeeeeeeeeeeeeeeerrrrrrrrrrrrrrrd!!! Thats pretty interesting though...
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06-04-2009, 10:21 AM	#4
Buehler445 Supporter Join Date: Apr 2007 Location: Scott City KS Casino cash: $-1385266	You didn't know that? I learned that shit in my HS physics class. -9.8 m/s2 is stuck in my head for eternity. WTF are they teaching you? Posted via Mobile Device
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06-04-2009, 10:22 AM	#7
damaticous lurker Join Date: Sep 2003 Location: home Casino cash: $9959900	Actually, from what I remember, the ball bearing in your hand would hit the ground first. when you fire a bullet from a gun the bullet tends to arch upward a bit, so it is actually falling at a different height from the one that is dropped. I could be wrong, but I remember reading that or seeing it on TV or something. Otherwise, yes, they'd hit the ground at the same time.
Posts: 1,358

06-04-2009, 09:13 PM	#10
Pitt Gorilla Banned! Join Date: Sep 2000 Location: NOT Columbia, MO 65201 Casino cash: $40194	Physics 101. Good stuff. __________________ Your son is a bench warmer because of your weak genetics not because of the coach Norlin Mommsen is disgusting.
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