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Errant 'Mythbusters' cannonball hits home in Dublin
contracostatimes.com ^ | 6 December, 2011 | Paul Thissen

Posted on 12/07/2011 6:54:14 PM PST by marktwain

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To: JRandomFreeper

You have a road tractor (and a class A license) to pull the trailer, or is it a goose neck rig that say, a 1 ton or better PU with a fifth wheel hitch could haul?


41 posted on 12/07/2011 10:14:05 PM PST by BlueDragon (there is only one "form")
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To: Political Junkie Too
That's by the Camp Parks Army Reserve Base
I didn't know that was still there. My oldest brother was in the Air Force and was stationed there around 1955.
42 posted on 12/07/2011 11:30:41 PM PST by lewislynn ( What does the global warming movement and the Fairtax movement have in commom? Misinformation)
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To: BwanaNdege

It’s been a long time since I took physics but as I remember it inertia was the tendency of a body at rest to stay at rest.


43 posted on 12/08/2011 4:30:21 AM PST by Hacklehead (Democrats define "fairness" as taxing the rich until they have no more than anyone else.)
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To: Hacklehead
It’s been a long time since I took physics but as I remember it inertia was the tendency of a body at rest to stay at rest.

Or in motion. To paraphrase Newton, inertia is the tendency of a body to resist a change in its state, whether it is at rest or moving at a uniform speed in a straight line.

Roughly speaking, because of inertia it will take the same amount of energy to stop a cannonball, as it does to fire it out of the cannon. Which is why they don't stop moving when they hit houses, cars, redcoats, and so forth.

44 posted on 12/08/2011 5:24:52 AM PST by RansomOttawa (tm)
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To: RansomOttawa

“It’s been a long time since I took physics but as I remember it inertia was the tendency of a body at rest to stay at rest. Or in motion.”

I forgot that last part, thanks.


45 posted on 12/08/2011 5:36:14 AM PST by Hacklehead (Democrats define "fairness" as taxing the rich until they have no more than anyone else.)
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To: BwanaNdege
"Inertia" in the sense of linear motion, is the layman's term of how an object resists changes in motion. But it's not really correct because there is no way to calculate inertia. What's the formula for linear inertia? What are its units? It you read through the physics page you posted, and thinking about how far the cannonball moved despite barriers, you'll find that they are actually talking about momentum: Momentum = mass * velocity. Or when they're talking about the resistance to a change in linear motion, they're simply talking about mass.
46 posted on 12/08/2011 5:42:18 AM PST by GOP_Party_Animal
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To: GOP_Party_Animal

http://www.differencebetween.com/difference-between-momentum-and-vs-inertia/

Momentum vs Inertia

Inertia and momentum are two concept involved in the study of motion of solid bodies. Momentum and inertia are used to describe the current state of the object. Both inertia and momentum are concepts related to the mass of the object. Inertia and momentum are relativistic variants, which mean the equations for calculating these properties vary when the velocity of the object approaches the speed of light. However, Inertia and momentum plays a very important role in both Newtonian mechanics (classical mechanics) and relativistic mechanics.

Momentum

Momentum is a vector. It is defined as the product of the velocity and the inertial mass of the object. Newton’s second law is mainly focused on momentum. The original form of the second law, force = mass x acceleration, can be written in terms of velocity change as: force = (mass x final velocity – mass x initial velocity)/time. In a more mathematical form, this can be written as change of momentum/time. The acceleration described in Newton’s formula is actually an aspect of momentum. The momentum is said to be conserved if no external forces act on a closed system. This can be seen in the simple instrument “balance balls”, or scientifically known as Newton’s cradle. Momentum takes the forms of linear momentum and angular momentum. The total momentum of a system is equal to the combination of linear momentum and angular momentum

Inertia

Inertia is derived from the Latin word “iners”, which means idle or lazy. Inertia is a measurement of how lazy the system is. Inertia of a system gives us the meaning how hard it is to change the current state of the system. The higher the inertia of a system, harder it is to change the velocity, acceleration, direction of the system. Objects having higher masses have higher inertia. That’s why they are hard to move. Given that it is on a frictionless surface, a moving higher mass object would be hard to stop too. Newton’s first law gives a very good idea about inertia of a system. It states “an object not subject to any net external force, moves at a constant velocity”. This tells us that an object has a property that is not changed, unless, there is an external force acting upon it. An object at rest can also be considered as an object having null velocity. In relativity, the inertia of an object tends to be infinity when the speed of the object reaches the speed of light. Hence an infinite force is required to increase the current velocity. It can be proved that no mass can reach the speed of light.

What is the difference between momentum and inertia?

- Momentum is a physically calculable property, while inertia cannot be calculated using a formulae.

- Inertia is just a concept to help us understand and define mechanics better.

- While, momentum comes in the forms of linear momentum and angular momentum, the inertia comes only in one form.

- Momentum is conserved in some cases. Momentum conservation can be used to solve problems. Inertia doesn’t have to be conserved in any case.


47 posted on 12/08/2011 7:31:34 AM PST by BwanaNdege (“Man has often lost his way, but modern man has lost his address” - Gilbert K. Chesterton)
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To: BwanaNdege
Thanks for the post - that really helped to set things in my mind for these two terms.

...and nothing describes the difficulty of stopping or starting federal programs like the term "bureaucratic inertia"!

48 posted on 12/08/2011 2:45:30 PM PST by GOP_Party_Animal
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To: BwanaNdege

How about....

ertia = moving
inertia = not moving
ertia minor = moving just a little

Thanks...and don’t forget to tip the waiters.


49 posted on 12/08/2011 2:59:05 PM PST by eddie willers
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To: lewislynn
U.S. Army Reserve: Parks Reserve Forces Training Area.

-PJ

50 posted on 12/08/2011 7:13:35 PM PST by Political Junkie Too (If you can vote for President, then your children can run for President.)
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To: eddie willers
How about....

ertia = moving

inertia = not moving

ertia minor = moving just a little

I'll have to add that to my dictionary of useful terms...

Just as soon as I get a...

Round Tuit

Right now I need to get "ertia minor" and go cook some breakfast. Thanks!

51 posted on 12/10/2011 5:51:49 AM PST by BwanaNdege (“Man has often lost his way, but modern man has lost his address” - Gilbert K. Chesterton)
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