PHYSICS & FORCES

GRagland

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Oct 7, 2002
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Does anyone know if there is a physics calculator (downloadable or web java app) that would allow me to type in all the forces acting on an object (friction, normal forces, gravity...) and it would tell me the net force, acceleration and all that good stuff. It would be really helpful to have some easy way like this to check my homework answers. I gotta show my work, so of course i gotta do it myself, but it would be nice to know if im doing it right by seeing if im getting the right answers... Anyone know?
 

PowerMacG5

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Apr 14, 2002
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A good graphing calculator should do this for you. All you are doing is working with vectors for the forces, and a graphing calc can add and subtract them. Although, you still need to find out certain info on your own. This can only be used to get the end vector, in your case the Net Force vector.
 

GRagland

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Oct 7, 2002
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Graphics calculators can prolly add vectors, but you still need to know the equations and process. Wish there was a program that did it all if i typed in the given information.
 

PowerMacG5

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Originally posted by: GRagland
Graphics calculators can prolly add vectors, but you still need to know the equations and process. Wish there was a program that did it all if i typed in the given information.

If this program existed, everyone would be a physicist. You should learn to memorize the equations needed and/or the ideas behind them. The reason I consider myself very good at physics is the fact that I can conceptualize the ideas. I don't need to memorize all the forulae, but I can actually "see" how come they exist. If you learn this skill of "seeing" the problem, I believe anyone can succeed in physics. The problem I see with a lot of physics students I tutor in my High School is the fact that they try to do everything mechanically. I believe that just trying to do something mechanically is not good. You should always be able to conceptualize a problem.
 

MegaloManiaK

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May 27, 2003
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Originally posted by: KraziKid
Originally posted by: GRagland
Graphics calculators can prolly add vectors, but you still need to know the equations and process. Wish there was a program that did it all if i typed in the given information.

If this program existed, everyone would be a physicist. You should learn to memorize the equations needed and/or the ideas behind them. The reason I consider myself very good at physics is the fact that I can conceptualize the ideas. I don't need to memorize all the forulae, but I can actually "see" how come they exist. If you learn this skill of "seeing" the problem, I believe anyone can succeed in physics. The problem I see with a lot of physics students I tutor in my High School is the fact that they try to do everything mechanically. I believe that just trying to do something mechanically is not good. You should always be able to conceptualize a problem.


1. Solving simple equations is not what makes you a physicist.
2. Graphing calculators can solve simple physics equations no problem, the hard part is breaking it down to simple vector addition
3. Math is by nature mathmatical, if you can derive formulas and not memorize them then go you, not being able to derive them is not that uncomon.
4. Anyone can suceed in physics if they take the time to learn how to do the math.
5. "Seeing" simple forces in a 2d highschool problem is notable, but that does not make you a master of physics. Visualizing a dynamic physics problem in 3d is alot harder and ive been forced to do some problems that use 4 and 5 dimmensions which can only be done mathmaticly with the raw coordinates.
6. He's not asking for a program to computer the forces and direction of a black hole, not to mention he simply wants to check his answers not solve the problems with it.

You need to have a good grasp of what the mechanical methods are representing, but saying that because you don't have to memorize equations makes you better at physics than someone who does is nieve.

Note: Im not going to spell check any of that so get over it spelling nazi's.;)
 

Triumph

Lifer
Oct 9, 1999
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Originally posted by: MegaloManiaK 5. "Seeing" simple forces in a 2d highschool problem is notable, but that does not make you a master of physics. Visualizing a dynamic physics problem in 3d is alot harder and ive been forced to do some problems that use 4 and 5 dimmensions which can only be done mathmaticly with the raw coordinates.


Wow, you've managed to solve problems in the 4th and 5th dimensions? Amazing.

 

QueHuong

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Nov 21, 2001
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Here's another post that still doesn't answer the original poster's question.

I'd like to know of such programs too...especially ones that can graph 3d vectors.
 

GRagland

Senior member
Oct 7, 2002
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On a slightly other topic... What does this physics problem mean?

- A spring of constant k is initially compressed a distance Xo from its unstretched length. What is the change in potential energy if it is then compressed to an amount X from its unstretched length?

Im not sure what they mean by Xo, does it mean X=0, in which case the spring would not be compressed initially. If so that would be a werid way to word it ("initially compressed a distance 0 from its unstretched length...") Anyone know?

part B of that problem is:

- Suppose the spring is then stretched a distance Xo from the unstretched length. What is the change in potential energy as compared to when it is compressed by an amount Xo?

WTF!
 

InverseOfNeo

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Nov 17, 2000
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There is a program my AP physics teacher in hs (5 years ago) used one...you set up the bodies that the forces are acting upone, tell it what you know and what you want to know and it tells you everything....I dont know the name of it though.
 

PowerMacG5

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Apr 14, 2002
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Originally posted by: Triumph
Originally posted by: MegaloManiaK 5. "Seeing" simple forces in a 2d highschool problem is notable, but that does not make you a master of physics. Visualizing a dynamic physics problem in 3d is alot harder and ive been forced to do some problems that use 4 and 5 dimmensions which can only be done mathmaticly with the raw coordinates.


Wow, you've managed to solve problems in the 4th and 5th dimensions? Amazing.


That's why I didn't even bother responding to him. Yes these dimensions exist, but you will never do them in any undergraduate physics class.
 

Giscardo

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May 31, 2000
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Originally posted by: GRagland
On a slightly other topic... What does this physics problem mean?

- A spring of constant k is initially compressed a distance Xo from its unstretched length. What is the change in potential energy if it is then compressed to an amount X from its unstretched length?

Im not sure what they mean by Xo, does it mean X=0, in which case the spring would not be compressed initially. If so that would be a werid way to word it ("initially compressed a distance 0 from its unstretched length...") Anyone know?

part B of that problem is:

- Suppose the spring is then stretched a distance Xo from the unstretched length. What is the change in potential energy as compared to when it is compressed by an amount Xo?

WTF!
Xo is just a number, doesn't matter what number. It's not zero, it was compressed from X=0, to a point Xo meters (or whatever units) from X=0.
TO find the change in potential engergy for part A you want to first find the potential energy when it is compressed to Xo, by plugging in Xo for X into the formula E = -kX^2 or whatever it was.

TO solve part B, they are saying that instead of compressing you pull the spring by the same distance. the change in potential energy is the same since the distance is the same? Even though the signs of Xo from partA and partB are different because they are in different directions from the uncompressed point, when you square X in the formula -kX^2, the sign goes away.

 

GRagland

Senior member
Oct 7, 2002
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Originally posted by: Giscardo
Originally posted by: GRagland
On a slightly other topic... What does this physics problem mean?

- A spring of constant k is initially compressed a distance Xo from its unstretched length. What is the change in potential energy if it is then compressed to an amount X from its unstretched length?

Im not sure what they mean by Xo, does it mean X=0, in which case the spring would not be compressed initially. If so that would be a werid way to word it ("initially compressed a distance 0 from its unstretched length...") Anyone know?

part B of that problem is:

- Suppose the spring is then stretched a distance Xo from the unstretched length. What is the change in potential energy as compared to when it is compressed by an amount Xo?

WTF!
Xo is just a number, doesn't matter what number. It's not zero, it was compressed from X=0, to a point Xo meters (or whatever units) from X=0.
TO find the change in potential engergy for part A you want to first find the potential energy when it is compressed to Xo, by plugging in Xo for X into the formula E = -kX^2 or whatever it was.

TO solve part B, they are saying that instead of compressing you pull the spring by the same distance. the change in potential energy is the same since the distance is the same? Even though the signs of Xo from partA and partB are different because they are in different directions from the uncompressed point, when you square X in the formula -kX^2, the sign goes away.

Ok so the change in potential energy (answer to part A) would be E= .5k(Xo-X)^2... no... I dont see how i can do this problem if i have no idea what Xo and X equal or how long the spring is or what K equals.... Please more help!

 

MegaloManiaK

Golden Member
May 27, 2003
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Originally posted by: KraziKid
Originally posted by: Triumph
Originally posted by: MegaloManiaK 5. "Seeing" simple forces in a 2d highschool problem is notable, but that does not make you a master of physics. Visualizing a dynamic physics problem in 3d is alot harder and ive been forced to do some problems that use 4 and 5 dimmensions which can only be done mathmaticly with the raw coordinates.

Wow, you've managed to solve problems in the 4th and 5th dimensions? Amazing.

That's why I didn't even bother responding to him. Yes these dimensions exist, but you will never do them in any undergraduate physics class.

Wow, just because you've never done it then it must not exist right.

Ever hear of calc3? It's not like thats some elite group of people who do it, millions of people go through a 4 part calculus sequence.

But im sure you'll now come back and tell me how you have a masters in physics blah blah blah.

Oh, i guess im the moron then because those who post on anandtech know everything.

That and your understandings of "dimmensions" comes from sci-fi, mathmaticly a dimension is a set of coordinates.

Edit: closed italics