Classical Physics

so this is a hypothesis i had concerning gravity and so called antigravity. it is my understanding that every object with any mass has a gravitational pull. it seems that for any type of true antigravity, an object would need to have a negative amount of mass. this of course seems impossible but then i started thinking about it more and thought of an interesting idea that involves antimatter. im not exactly sure how antimatter works but it seems that since mass is the amount of matter an object has, would an amount of antimatter mean that you had negative, or "antimass?" if you would get a type of "antimass" wouldnt that generate a force that was opposite that of gravity?…

Now, before I ask, I know about moment of inertia, or rotational inertia, and I know you may bring that up to answer my question instead just regular inertia. I do not want this question to be answered with the mentioning of moment of inertia. I just want regular, linear inertia to be part of the answer instead. So for the question, how does inertia, the resistance to acceleration (or change in velocity) affect how spectacular, amazing or cool the routine or trick is when a gymnast is performing those stunts? How does inertia affect the overall routine and performance a gymnast does in the air, or tumbling or something else?

http://www.kloonigames.com/crayon/ This is just beyond awesome... I feel like getting a touch-screen computer JUST for this game... finally, science education *FUN* game. brilliant. Had to share. ~moo

Rocket A and Rocket B are traveling next to each other in a straight path away from the earth. Both rockets are so far from earth that the affects of gravity are negligible, we only need an arbitrary reference point in space. Both rockets are initially moving at 10 m/s away from the earth and the mass of each rocket is 20 kg. The equation for kinetic energy is given by 1/2 x mass x velocity^2. Thus an observer on earth, the kinetic energy of each rocket is 1/2 x 20 x 10^2 = 1000 joules. From Rocket A's perspective, Rocket B has 0 kinetic energy because the two are moving side by side at the same rate. The reverse is true of Rocket A from Rocket B's perspective. As…

Hi guys!! New question: Is atomic spacing constant?, take copper in example. If it's not what is the explanation of those changes in general?

Two water-filled buckets with holes in bottom hanging from strings. One swinging one not. Which empties first? Two identical buckets each filled with water. One set swinging from side to side and the other stationary. Which one will empty first, and why? Or will they empty at the same rate? Assume no surface tension or evaporation effects. Swing is 45 degrees either side (not over the top)

I want to roll a ball (made out of the best material) over a flat surface of some kind to create the most static electricity I can. What material do you think I should use? ___________0_______________

Hey, this is actually a lab I am designing, and I've run into a few problems that I can't seem to figure out. I will be having 4 neodymium magnets attached to me (2 per shoe) with there being a switch to allow/turn off an electrical current to the magnets. I also have a sheet of steel, which I will step onto. Now, when I step onto in, the magnets will be attracted, but when I flip on the current, behold they repel, and propulsion is created. My problem is that, in designing I overlooked the fact that, normal steel, will attract both poles. Which puts a major kink in my plan. I was wondering if anyone knew any techniques to make the steel act like a ma…

Been thinking about relativity. I read that the reason A. E. came up with the theory was to explain the seeming paradox of a constant light speed independent of the speed of the light's source. I've no scientific training or background whatever, so I'm sorry if this is stupid, but... What if light emanates outward from a source at a range of speeds and the light we can see and measure is simply travelling at the right speed for our senses to pick up? It would mean that light would always appear to travel at a constant velocity. If there's anything to this idea, it might explain why all of the formulas predict that nothing can go faster than light. As an object ap…

What would one use to change the direction of a wave front at an interface between two media and returns to the medium from which it originated? There are radio waves, UV rays, IR wave, Radar waves, Lazers, even solar rays....... What would you use to refect it back?

If machine A were to lift 1000 kilos directly, and machine B were to use a lever for better advantage in lifting the same 1000 kilos, would machine B spend less energy? The machine can be a robot, and the lever is some tool it found laying around.

I was reading the book "General Chemistry" by Linus Pauling and i stumbled upon a confusing part where it explains the IS units of coulomb. The book explained Coulomb; "The coulomb is one-ampere second, and the ampere is defined as the current in each of two infinitely long parallel wires 1 meter apart that causes an electromagnetic force of 2 x 10^-7 newton per meter of its length to act on each wire." as quoted from the book. This definition i did not just get from the book, i searched up online and the other sources also said infinitely long parallel lines. I am confused at the "infinitely" long parallel wire part. What is this infinitely long parallel wire?…

Is there anyway to get the frequency of notes (from a midi or wav)? Through matlab or other softwares perhaps?

Hey! I'm new to science forums, and I need some help on a project of mine. I am making a electrically powered helicopter, ride-in size. I have the circuits halfway designed, but I need to know how many rotations per minute it takes to achieve certain amounts of lift, and how many volts it would take to turn a motor at certain speeds, so I can use the resistors with the right amount of Ohms. If anyone is concerned about safety issues, I'm not going to try to fly it until I learn how. If I can design a working helicopter, I might be able to get a scholarship later. I'm wanting to go to college and get a good degree on engineering. By the way, what college degrees do they ha…

Actually I was thinking about how to make a bicycle function without chaine may be by applying a magnetism principle( attraction??) between the 2 wheels. Do you think it's theoretically possible? which mechanism might need to be developed/experimented? physics theories to apply?

Hi, I have been viewing some physics lecture videos and have come across a notation that is not familiar. Any help will be appreciated. The following is part of an equation for wave motion: ε(epsilon) φ(phi -with 2 dots above it) = c^2÷ε [(φ sub i - φ sub i+1)+(φ sub i - φ sub i-1)] φ(phi with a dot above it) and φ(with 2 dots above it) What do the dots above φ indicate? Thanks, Tom

In order to show unpolarized light we use the can you tell me please about what this arrow on the unpolarized represent whether it represent electric field or what?

What is the power neccesary to throw a ball vertically up against gravity? Lets say we want to know how much power a human spends on throwing a ball up. Lets say we know the work done W1 (from the bottom to up phase of the ball), and we also know the work done W2 (from top to bottom of the ball). Lets say that we also know the time it takes for the ball to go up T1, and also the time it takes for it to go down T2. The two individual terms should be equal in both up and down phases respectively for the conserved system. But since this system is conserved and in a closed loop, is the total work of the system zero (W_system=W1+W2=0)? But then Power spent shouldnt be …

A biker rides on a motorcycle down the hill, and the motocycle exerts a force of F1 down the hill. The motorcycle also has mass, and therefore there is a gravitational force F2 acting on the motorcycle down the mill. The bike travels a distance D1 down the hill. It took the motorcycle time T1 to do so. What is the power required by the motorcycle to perform this? Is the power consmed by the motorcycle: Power1=(F1*D1)/T1 ,or is the power consumed: Power2=((F1+F2)*D1)/T1 I guess my question is, Net Power is not the same as the power consumed by the motorcycle motor right, because net power is Power2 but the motorcycle motor provides only Power1, right

I'm hoping this isn't speculation as it's part of a SF plotline I'm playing with and I want it to be as good as Clarke's stuff We know the slingshot effect works from various spaceprobes that have used it. We know (theoretically) that the space elevator works. So....if you had a ship in geosynchronous orbit, on the end of a space elevator, and then rapidly shortened the tether from the ground before releasing it, it should impart a slingshot effect on the ship? Basically the energy put in by the power station on the ground would accelerate the ship without having to carry all of the fuel into orbit? I'm pretty sure it works in theory (and the practica…

I don't know to solve this homework and i need a little help Diver at a depth of 20 m below the water breaths 1 liter of air. With what acceleration the air bubble begins to move against the surface ,how his speed varies with time and what is its volume at a depth of 5 m? The water temperature is 20 ° C. Part of a solution will be need to find numerically. Thanks in advance

newton's 1st law states that acceleration can only be acheived if an external UNBALANCED force acts upon an object newton's 3rd law states that forces ALWAYS occur in pairs so how can there ever be an UNBALANCED FORCE?

So I learned in physics what the first (mass) and second (inertial) moments are, but I am lost in what the actual concept of a moment is, devoid of the qualifiers. What is a moment?

A flying fish leaps out of the water and glides for up to 30 seconds. Does anyone know the equation for this. i.e. the surface area to volume ratio to stay in the air for a while.

For a given optical system, there always a term called resolution power. It is called limitaion caused by diffraction. I have known the equation sin(theta)=1.22lambda/ampture. But not really understanding the meanings. Can anyone give a comprehensive explanlation about the resolution power or diffraction limitaion?