Classical Physics

I have just watched a news video of a Soyuz rocket taking off from Baikonur and noticed that there is no trail of smoke like you see on the American launchers. It left the sky quite clear. Why is this?

Hey guys, I was talking to a friend of mine and the subject of a slinky came up, specifically if and how the movement of a slinky can be represented with physical formula. I thought it could be an awesome challenge, but I'm not quite sure where to start. I figured this will probably be best by starting with Lagrangians - last semester we managed to represent relatively complex systems with them - But we did that with either rigid objects (which a slinky isn't) or with ropes and strings that had a relatively simplistic movement (either extended downwards or sideways). A slinky, well.. not sure how to start. Also, obviously it starts with some momentum at its to…

In this wikipedia article the orbital element the "specific relative angular momentum vector" h is defined as: h = r cross v where r is the position vector and v is the velocity vector. In two dimensions this is the normal dot product of r and v: h = r.x * v.y - r.y * v.x The trouble is that counterclockwise orbits have negative h values. Is this correct? Cheers, Mike

I was reading from this website http://www.fuellesspower.com/6_Gravity2.htm That you can create electricity from this machine. Thats quite interesting, it seems that you have a never ending energy source. So my question is, Is this true? Is it possible to make a machine such as this? It seems to me it should be, and im going to try when i get home today. If so, then were is the energy coming from? Bent space causing gravity? Then that means that energy can come from nothing, does it not? Also, i dont see why this is not applicable to a car. Just have multiple, relatively small versions of these all conected to the axle, and always going. The wheels would be attached …

At http://news.bbc.co.uk/1/hi/sci/tech/8040073.stm there is a diagram which shows the Herchel and Planck spacecraft orbiting the L2 lagrange point. I am puzzled by this as there is no solid body with any mass in which to orbit around. Could somebody please explain what is going on to a non-scientific mind? Thanks.

I'm in my beginning college physics class and I wonder why F = MA works sometimes. It get repeated over and over again from every grade since forever so I've just.... used it without question. Why is it that when particle 1 is moving at a constant 1 million mph and has mass of x (whatever) and collides with particle 2, that no force is applied to particle 2? Or why is this logic flawed?

Hi, first of all I'm new here and ready to learn! So I'm sorry if my questions seem stupid and please correct me if I'm wrong. My question is this: When multiple forces of different speeds that share the same mass act on a single point, how do you calculate the force applied? An example would be a martial artist going in for a punch, and there are three places where he exerts force, the extension of the arm, the jerk on his upper body and using his legs to propel him forward but only the fist connects to the person he is punching. My teacher told me to simply add the forces up and I'm skeptical of that. As F=ma, the mass remains but the speed of these forces are …

Charging battery is pushing back the electrons to the battery, and what is the different between a rechargeable battery and a non-chargeable battery make them can be charge and another one can't ?

Determining absolute motion with momentum measurements Two inertial platforms move parallel and relative to each other – how do observers on each frame determine the absolute velocity of the other where the relative speed of the frames is V? Each frame is equipped with momentum balls (mbs) having mottled surfaces. Along the length of each frame and facing each other is a lengthy strip of a flat mottled surface suitable for bouncing the mbs... Frame R, moving right releases a few mbs perpendicular to the mottled surface on Frame L moving left relative to R. There are three cases. 1. L is at absolute zero velocity wrt to R; hence R contributes all the velocity t…

I've been thinking; Why not make hydrogen via solar panel and battery: To heat home, Cook and or heat water. What I did find out, is that there is such a thing as a hydrogen compressor. And that tube bending is done with a hydrogen stove by neon light makers and solar panels are obtainable as well. Is this a good place to find out more about what I'm working on? Like how big of a panel is necessary? Converting stove into heater for house?

The kinetic energy that an object possesses is dependant on it's speed according to the equation E=1/2 mv^2 So wouldn't a loss of energy mean that the object has slowed down and lost some momentum?

A sailboat tilts considerably with strong wind. Could a sailboat fitted with an inverted T keel, the horizontal 'wings' capable of independently adjusting pitch, force the hull to stay level ?

Help! I've been trying to get a positive number on my multimeter for the resistance in a circuit. However, I keep ending up with either 1 or negative ohms. Switching the leads gives me either the 1 or a negative number. My circuit is closed as well, and I have various resistances. How can I get my multimeter to read positive ohms? Or can I assume the negative number would be the same if it were positive?

This is a hw problem so please explain your process instead of telling me the whole answer, thanks! There is a conductive ball hanging from a string in a electric plate. As you can see its slightly tilted toward the negative end. mass of ball: 0.04g potential difference: 480V separation of plates: 0.06m angle of string hanging: 20 degrees the question asks: What is the charge of the ball? I drew a free body diagram of three forces. one: force of tension two: gravity/weight three: force of charge pointing towards the right I think I'm suppose to add up the three forces to equal zero. F1 + F2 + F3 = 0. I think F3 should use the form…

Hey all, Let [math]M_A[/math] and [math]M_B[/math] denote the masses of objects [math]A[/math] and [math]B[/math], and let [math]R[/math] denote the distance between them at [math]t_0[/math]. Is there any way to calculate the instantaneous [math]F_G[/math] acting upon the two at time [math]t[/math] (from a Newtonian perspective)? What confuses me is that the distance between them changes with the distance traveled, which in turn changes according to the force acting upon the two, which in turn changes according to the distance between the two, and on we go in a vicious circle. What I'm a little afraid of is that I'm touching upon the n-body problem, but I'm not sure, tha…

In the absence of a diagram my question may be a bit hard to follow, but I'll do my best... Imagine I have a barbell floating in empty space - ie two equal weights connected by a rigid bar (a single rigid pole would do as well, but the barbell might be clearer). I start it spinning on an axis that passes through the center of mass of the system (ie, middle of the bar) but is neither parallel nor perpendicular to to bar. My intuitions as to what will happen lead in contradictory directions:- 1) Centrifugal force will cause the spinning barbell to straighten out so that the axis of spin becomes perpendicular to the bar; 2) Conservation of kinetic energy and angul…

does thought have gravity

A friend of mine noticed that the units of torque, N x m, should be the same as the units of work, again, newtons times meters. Yet torque is expressed in newton-meters and work is expressed in joules. What's the difference? I think it has something to do with the difference between a cross and dot product, but that's just conjecture on my part. Thanks! N

ok...now i personally belive that some day very soon that law of conservation of energy is going to prooven wrong.......my question is from where do atoms get their energy to continously survive??wont some where down the line energy have to be created??

ok i was staring at a fly in my car oneday and then i was like...... why dosint the fly fly to the back window. so the car is drinving 75 mph. and the fly is going 12 mph why dosint the fly start flying bacwards to hith the back windshield. and if the car is traviling 75mph and the fly flys forward in the car wouldint that mean the fly is moving faster than the car

Hi all. Before i ask my question I will explain my thought process so you can point out any errors. I was thinking about the way that TV shows represent the gravitational effect of planetary bodies in space. Usually with a ball on a piece of fabric showing a curve in space-time. It suddenly occured to me that it was so simplified that it didnt satisfy my curiousity. I tried to visualise how this gravitational effect could be represented as it works in reality i.e. rather than just on a single plane that a piece of fabric represented, but how it would look on all degrees around a sphere. Really hard lol So I moved on to wondering how small the the center of …

I never quite understood why the force of friction between two surfaces is independent of the area of contact between them. It seems to me that it should have a directly proportional relationship, but in physics we always used the equation [math]F_f = F_N \mu [/math] which doesn't take any sort of area into account at all. What's the deal?

I am sure that the following will be interesting to be seen. http://www.youtube.com/user/savata71 These are computer simulations ( I have made with MSC Visual Nastran 4D) of a gyroscopic device that overcomes gravity. And these simulations say it works. So, what you think?

Imagine you had a strong magnet and two metal spheres of neutral charge. Could you charge them by induction if they were brought in contact, then the magnet was brought close to one of the balls (classic induction scenario) Basically, can a magnet be used as the charged object that moves the negative charges around? I would try it out myself except for the fact that its really humid here right now and I'm thinking that the charge would bleed off faster than someone can respond.

I'm trying to understand Newton's Third Law of Motion: for every action there is an equal and opposite reaction. If a rocket does not push on air than what drives it? Is it internal pressure in the Combustion chamber ? When the gas escape pushes on gas accelerating it backward then the gas must therefore push forward on rocket:eek: The mass have be the same? Small mass cannot move big mass it has be the same mass.