Classical Physics

We had to conduct a similar practice to Millikan's oil drop experiment in class. This is the situation: There are 10 bags each containing a different amount of small marbles of the same mass. There is also one big marble of different mass to the small marble added to each bag. Each bag is massed and that mass is given to us. Now through techniques similar to those of Millikan, we must: 1. Determine the mass of one SMALL marble. 2. Determine the number of SMALL marbles in each bag. Does anyone have any suggestions in terms of what method to use? I have one method that works in theory but is prone to many errors and discrepancies in the result. This method doe…

Maybe I can find fame with the Albers accelerative driving force. YOU CAN BELIEVE IT BECAUSE IT'S TRUE, as a gospel preacher said. When you enter a turn there is a second sideways shear force on the tires and car and road proportional to how fast you are changing the steering wheel position. This is IN ADDITION TO the momentary centrifugal force which is proportional to the turn radius at the moment. This is important, because it says that if you need to make a sudden veer, if you jerk the steering wheel rapidly you induce a momentarily high shear force sideways and compromise traction. I have caught myself doing this as I come back into lane after passing. It is …

Hi there, I was looking for any insight into the following problem: Q: Jane wishes to quickly scale a slender vine to visit Tarzan in his treetop hut. The vine is known to safely support the combined mass of Tarzan, Jane and Cheeta. Tarzan has twice the mass of Jane, who is twice the mass of Cheeta. If the vine is 60.0m long, what minimum time should Jane allow for the climb? Any help would be greatly appreciated, K

Take a parallel plate capacitor, area A and distance d. I know that E=sigma/e0, V=Ed, C=Ae0/d. I have also shown that the energy stored is 1/2CV^2=(e0/2)(E^2)(Ad). Now, if I increase the distance between the plates by an amount x, then E doesn't change and the increase in energy is (e0/2)(E^2)(Ax). But the work done by increasing the distance is Fx=(QE)x=A(sigma)Ex=e0(E^2)(Ax). Not equal to (e0/2)(E^2)(Ax), but twice that!! What's going on here!?

Sorry if this seems obvious, but I'm a bit confused how it's possible to locate the epicentre of an earthquake using the method of recording the speed of vibrational waves to a seismometer. If the only true test is using an earthquake to acquire the data, how is it possible to do preliminary tests to work out the speed of a wave through earth size masses of compressed, and fluid rock. How did they determine the start of an earthquake, and the speed it takes the wave to hit the seismometer, when (at the time) there was little knowledge of the quantities of certain rock that make up the mass of the earth.

Just a simple question. Say we have 2 tubes. Air goes through a normal tube at a certain rate. Then we have another one, with a device to create a vortex - and the air goes through it at the same rate. Will air in the one with the vortex go faster [in the tube]? and Will it go through more smoothly? thank you

I`m considering buying a new (and bigger) Power Kite, I was wondering if anyone could give me an idea of "Lift" / "Pulling power" a 3.2 metre x 1 metre kite might have in say a gentle 10kph wind. thanks

I have a question here A rectangular plane loop with dimensions 250 mm by 180 mm is pivoted to rotate about the z axis. The long side of the loop is along the y-axis and the plane of the loop makes an angle of 45 degrees with the y-axis. If a uniform magnetic field of magnitude 300 mT is in the y direction: (a) Determine the magnitude and direction of the force of each side of the loop. (b) Determine the torque about the z axis. I know that F=BILsin theta and Torque=BAIsin theta my problem here is how to get the current I

How can I Compare the magnitudes near the earth’s surface of the weight of an electron and a typical magnetic force exerted by the earth’s magnetic field (B = 10-5T) on an electron with speed 10 m/s. As I understood Weight of electron = mg Magnetic force=qBv am I right?

Please can anybody help me on this? The magnetic force on a moving electric point charge is given by F=qv*B where v is the velocity of the charge q and B the magnetic field. Derive the components of the magnetic force Fx, Fy, and Fz.

Our talk on eye lenses clued me to the fact that I have a poor overview of light absorption. It is a complicated subject, starting with, say ordinary matter with typical atomic spacing of an Angstrom or so. Am I correct in this, speaking of solids? CRC tables had that number if I am. Visible light is maybe 5,000 A, so in a discussion where highest frequencies are ultraviolet, the light wave is still longer. Interaction changes so strongly down through different ranges. I've been through much of this but I need to feel what are the different regimes and why because I have launched a thesis of fractional photons, dark energy. I figure I had better get clear (heehee)…

Was wondering if some of you physics kids could help me with a small problem... I need to know how to model the impact of a human body (or any projectile for that matter) on a reinforced concrete wall to be able to answer questions like: How much energy must be put into the action to generate enough force to push/throw something through a wall? How much damage will the wall/person take? Where does tensile strength enter the equation? etc.etc.etc.etc. I'd appreciate any help, thanks. -J Ps. Please bear in mind the fact that I'm a biochemist when you answer

well my physics class was assigned some homework the other day, and not even the teacher knew how to do this question (i live in a very small town ) anyway if anyone can help me out with this : "An unmarked police car, traveling a constant 90km/h, is passed by a speeder traveling 140 km/h. Precisely 1.00 s after the speeder passes, the police man steps on the accelerator. If the police car's acceleration is 2.00 m/s^2, how much time elapses after the police car is passed until it overtakes the speeder (assumed moving at a constant speed)?" Umm I just noticed there's a homework forum, eheh sorry

Hello, I'm having a bit of difficulty with this one mechanics problem, and I'd appreciate any pointers. So without further ado... "A thin semicircular hoop of radius R and mass m rocks back and forth without slipping on a rough surface. Find the period of oscillation for small amplitude oscillations, reducing to lowest order in oscillation angle theta. Then find the period if the surface is frictionless." Oh, and the center of mass is 2R/pi below the center of curvature. Thanks in advance.

im constructing a jumper (entire device must jump + lands as one piece) that can only be powered by springs and/or elastics.. it has to jump straight up and land with in a 1m x 1m box... so it's basically gravity + air resistence VS spring/elastic forces. Also, it has to be released by one person at least 1m away (ex: release with a string) the goal is to jump as high as possible I am not sure what is the best shape, mass, and material of the jumper I am thinking of making it a rocket shape from a pen..and wrapped it with aluminum foil (because it's more smooth than plastic?!) I think the frontal area should be as small as possible, but should it be slightly ro…

Hello all! first of all I would like to say this is NOT homework , I know that's probably what everyone says but its true. I actually thought up this question myself (yes I have time on my hands ) but have not been able to solve it. I'm in Calculus right now, but finished taking grade 12 physics last year. Needless to say I'm a bit rusty, which is why I need help on answering this... I'm not sure if anyone here knows what I'm talking about but the playground near my house has a big concrete cylinder thing to play in. This problem makes more sense if you keep in mind lol A 35 kg child in a 3 m radius cylinder concrete thing ( ) slides down from the left side at th…

I'm back with another strange question. and agian I hope this is the right topic area. I'm wondering if there is any way to cast a lighning bolt. big or small. if so, does anyone know the basic components needed for such a device? what I'm trying to do is create a weapon in my story that shoots a bolt of lightning. but I need some basic idea of how the thing would work so that I know how I should design the look of the weapon. Thanks for being here!

I have conducted a experiment to measure water displacement using a variable resistor. However i am now stuck, is there a equation to convert resistance into water displacement. i also have the water level im ml. any help would be much appreciated, thanks alot, hwk

dunno if this has been covered before .. lets say your sitting in a train ... the train is moving at the speed of light and there is a mirror in front of you ... you cant see your reflection because the light that bounces of the mirror would have to travel at twice the speed of light to get back to your eyes ... soo what do you see in the mirror ... and another question ... can you even see the inside of the train, or your hands and feet when travelling at that speed ... cause it seems all the light in the train should be moving the same direction or something like that ... so it cant hit your eyes for you to distinguish anything ...

Someone told me that black holes had dark matter in the center or otherwise contained dark matter. Is this true? I know dark matter is hypothectical and not proved, but has it even been hyposthosized that it is in black holes? This confused me.

E = .5*m*v^2 I have a problem with this formula. To illustrate lets play some mental catch with a friend. Assume I have a ball weighing 1 Kg and that I can throw it 10mps. When my friend catches it he will absorb the 50joules of transitional kinetic energy that my arm had imparted to the ball. My arm gets tired and I board a train and my friend remains by the track. (Didn’t I mention that we were playing catch next to a railroad track that goes in a big circle? Well we are…) The train is traveling at 10mps and as I pass my friend I drop the ball so he can catch it. Again when my friend catches it he will absorb the 50joules imparted to the ball by the tra…

hi a question: is -0.5 half as large as -1, or is -0.5 twice as large as -1 this came up on our physics test... since -0.5 > -1, meaning -0.5 that its larger than -1, so saying something that's half as large would imply that its smaller? which clearly isn't the case....

This 'thread starter' should probably be in the 'Speculation Forum', but nonetheless here goes: Just because 'classical mechanics' by-in-large represents the 'earliest' of our competing explainations of the physical world does not necessarily mean that it is the least valid. Might not QM reasonably discribe the world of the very small, classical mechanics the most macro, with relativity occupying a connective position 'relative' to each? aguy2

As far as I understand, the Moon and the Earth are tidally locked and there is a continual decrease in the energy of the earth-moon system (why is this btw?). Apparently this results in the moon moving progressively further away from the earth. this is counter intuitive to my mind, as i thought a loss in energy and angular momentum would result in the two bodies coming closer together?

I teach classes in basic thermodynamics to technicians the power production industry. In a class that I teach we define the following: Mass as: Amount of matter an object contains. And weight as: Force exerted by the mass when it is accelerated by gravity. A student of mine questioned that statement: How is mass resting on the earth being accelerated? So then we looked up the definition of Accelerate and found the following: "1. To cause to move faster; to quicken the motion of; to add to the speed of;" and it didn't seem to aid me in my explanation. I did find the basic description of gravity to be an attraction caused by mass. But then he aske…