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mostly what I need help in is the difference between stuff and the math. like, for instance, for some reason i always get kinetic and potential energy mixed up. Also I get where certain #s go (like, temperature's,wieght)mixed up also. if you can pleaeaeaeaease help!

thanks

Hmm. Let's see. What exactly do you need explained? There are quite a few physics nerds around here that could probably help you out. I don't know that we have a forum specifcally for tutoring, but I don't think it's a bad idea. Let's see, you need to know that difference between kinetic and potential energy, right? Well, let's start here:
* Energy is the ability to do work.
* Kinetic Energy is work associated with motion.
* Potential Energy is energy that matter has because of it's position.

For example, let's take water up in the mountains. If that water is stuck behind a dam, it's potential energy, because it has the "potential" to do work. Where as if that water is going over a waterfall, it's kinetic energy, because it's "mass in motion."

Does that help? (And any real physics nerds feel free to correct me. )

You need conversion charts for temperature and such? Is that the math part of it ithat's messing you up?

Kinetic energy + Potential energy = total sum of energy

if you hold a ball still it have only potential energy, but when you drop it the potential energy changes to kinetic energy. the ball has only full kinetic energy when it has reached top speed, when not it has some of the potential energy left but its gradually changing to kinetic.

do you need help with the formulars - how to calculate the amount of the kinetic or potential energy??

Maybe put up a sample problem, and show us where you're getting confused. One thing that you can do is work out the problem using the units only, and temporarily neglect the numerical solution. This will ensure that your answer uses the correct measure (instead of memorizing which SI units are applicable to which problem).

Help! I need to know as much stuff as possible on platinum as possible in the next few days! Please Save me!!!!!!!!!!!!

It is typical to start a new thread for new problems, but what do you need to know? Web Elements http://www.webelements.com/ has most of the information you would need for a High School class, so would the Encyclopedia in your school's library. Other than that, I can tell you Platinum is a silvery precious metal that does not tarnish under normal conditions. It is an excellent catalyst for many chemistry applications, causing it to be highly prized for both its beautiful and untarnishing lustre and its usefulness. It is used in expensive jewelry, and is more expensive than gold or silver.

i did a report on platinum once. puritan did a good job summing it up, just wanted to add that the name comes from the spanish word for silver.

also, i know that it specifically catalizes hyrdrogenation of a double/triple carbon-carbon bonds in organic reactions... we did that one in lab

:edit: put simply, that last part means it takes the carbon-carbon double or triple bonds and makes them into single bonds

Lynx wrote:i did a report on platinum once. puritan did a good job summing it up, just wanted to add that the name comes from the spanish word for silver.

also, i know that it specifically catalizes hyrdrogenation of a double/triple carbon-carbon bonds in organic reactions... we did that one in lab

:edit: put simply, that last part means it takes the carbon-carbon double or triple bonds and makes them into single bonds

Ooooooh! That really does help thanks for the info!

hmm... I've always thought of it this way, an object has potential energy when it has the "potential" to gain energy (rock on a cliff, soda shook up in a bottle, two nicely sized masses of uranium) it doesn't neccesarily have to obtain this potential, it only has this potential. If moved or disturbed for instance you no longer have the potential (vaporize the rock, freeze the soda, dilute the uranium). However, kinetic energy is what happens when the object obtains some or all of its potential energy 1 second after, (the rock is kicked of the cliff, the soda bottle is opened over your friend,... KABOOM). Finally note that the term kinetic is associated with mass moving, a change in position with time. There are other types of descriptive terms associated with energy such heat (friction), electromagnetic (light) and gravitational (gravity waves) but these aren't normally discussed in high school math.

where do the #s go? force numbers go in F, mass numbers in m, accelerations in a, distances in x,y, z or d, speeds in v, times in t, temperatures in T, momentums in P, pressure also in P, torque in tau greek (looks like a subscript T with a ~ for the top), radius is r, diameter is also d, period is T, frequency is lowercase omega (w with round corners) when in radians, f when degrees, amplitude A, E is energy, E is electric field, c 3.0*10^8 is speed of light g 9.80665 m/s^2 is gravitational acceleration, G is gravitational constant, q is charge, k is a general constant for electric forces, fields, spring constants... you name it, but for electricity 1/(4*pi*epsilon_0) is also good, h_bar good for quantum mechanics, (if you are working with the schrodinger equation... God help you). h is the same times 2*pi, (good for energy per photon of light of a certain frequency... can't think of any more though at this time. Umm as for units I don't have time at the moment but if this is what you were looking for good luck,

Later,
Pascal

Potential Energies are 'hiding' in the object, rather than in motion.

Some potential energies include the torque or compression stored in a spring of a mousetrap which has been set, or a fully charged capacitor or a charged battery at rest on a lab bench. The stored electrical energy can be turned into other forms like heat if you short it with a wire which becomes WARM, or sound, like if you power a radio with the battery.

'Springy' potential energy stored in a material is actually like the physical force of two magnets, except that atoms in a bond repel being smusshed TOO close together and ALSO attract if they are pulled apart from the ideal distance. So it's like a spring at rest which has a natural compressed length. If you squash the spring you store energy and if you stretch it apart longer than its natural length you are also storing energy.

This is how a catapult can store many men's back muscles worth of energy all wound up in the skein of rope. Then when you lob a boulder, you change the potential energy in the ropes into kinetic energy of a rock in motion - which hits the peak of its trajectory (Changing velocity for height - potential energy) and then picking up speed as it smashes into the enemy fort. (kinetic energy again which gets used up as impact energy busting up whatever it crashes into.) If the fort is up on a hill, then the catapult had to put more energy in than was used up - it left the siege engine moving faster than the speed it hits the fort. The guys up at the fort can ROLL the rock down on you and you would get the rest of the energy BACK, in the form of the rock rolling over all the guys at the catapult.

Medieval physics can be FUN, right? (OK how about the trojan rabbit in 'Monty Python.' )

The weirdest form of energy I studied is surface energy: the concept that the SIDE of an object is a form of energy, so a block at rest on a table has less energy than all the pieces you get if you smash the block into several bits with a hammer. Part of the work you did with the hammer got spent in creating all those new surfaces, but (if I understand this correctly - I probably have this wrong!) energy can be released if RANDOMNESS in increased (entropy.) Somewhere in that lecture was how thunderstorms get their electrical energy because of the zillions of random surfaces created when vapor in the cloud condenses into droplets or flakes. Any hints on this?