Difference Definition and 1000 Threads

So I'm kind of confused. The way I understand it, an electromagnetic field is just a regular electric field viewed from a relativistic point of view, meaning that since we see the charges moving relative to us, we feel like the particles and the fields created by them come closer together (I...

What is the difference between 'equivalent and equivalence'?

Homework Statement A cylindrical conductor of length L and radius R, L » R, carries a charge Q. 1. Neglecting boundary effects; evaluate the potential difference between a point at distance r from the center of the cylinder, and the center. Assume r to be of the same order of magnitude as R but...

Homework Statement The figure shows part of a complete circuit. The potential at point A is greater than that of B by 19 volts what is the potential difference in volts across the three microfarad capacitor? Homework Equations All relevant to electric circuits The Attempt at a Solution From...

Homework Statement [/B] I encountered this problem during my exam. A coil of 50 turns, each with area 0.02m2 is rotated in a uniform magnetic field of magnitude 0.4T. The coil is rotated at a frequency of 60Hz. Given the average power generated is 50W, what is the resistance of the...

I have seen so many questions and confusion about the difference between angular velocity/speed and angular frequency. Usually, answers were always given in the context of uniform circular motion (angular speed) and simple harmonic oscillation (angular frequency), but this is what causes the...

What is the difference between a red object at room temperature and a heated red object (Metal for example). They are both red except one is cooler then the other? Why aren't the red objects in my room not hot like the heating of a metal?

So we know that the E-field between two parallel plates is constant and that the potential difference between the plates is just the E-field times the distance between the plates. Let's say we're moving a positive charge from a negatively charged plate to a positively charge plate ( or near)...

Homework Statement There is a uniform electric field=100 V/m inclined at 45 degrees with the x axis. My doubt boils to which is greater? V(0,0) or V(10√2,0) (since my answer has the wrong sign) Homework Equations All electrostatics formulas The Attempt at a Solution The work done to move a...

Hello, I have two rebar samples of virtually identical chemical composition of 0.27 wt%C, 1.2 wt%Mn and 0.033 wt%V that are A706 grade. The rolling mill parameters are essentially the same yet I am seeing differences in pearlite size upon microscopy. The billets used to make the bars are...

Is there any difference between setting petrol on fire directly(by contacting it with burning stick) and heating petrol in a vessel, increasing its temperature above itself ignition temperature and making it burn spontaneously? What is the difference between flash point,fire point and self...

Is there any difference between 1 mole of CH4 and 1 molecule of CH4? or they mean the same thing?

Please teach me the difference between second quantization and QFT?

What is the difference between log and ln?? [Thread moved to General Math forum by moderator]

What is the difference between parallel and antiparallel spins for a pair of nucleons? My understanding is that nucleons have a strong tendency to pair - proton with proton, neutron with neutron, proton with neutron. When they pair their spins either: cancel (spins pair antiparallel) pairing...

What's the difference between Euclidean & Cartesian space?

In both the cases, the flow cross section area of the pipe is reduced.But in case of nozzles the velocity increases,pressure reduces and the flow rate is maintained.But in case of flow control valve, flow rate changes.(Assuming the fluid to be incompressible) Why is there a difference between...

In carburetors, at the throat or ventury, the area decreases and so velocity of air increases (by continuity equation.).This is reason for suction of fuel from the float chamber.But in case of throttle valve, when the valve closes(area of flow reduced), the quantity of air fuel mixture passing...

For my understanding there should be no big difference in i-v curve between regular p-n junction and p-i-n junction, the only difference i can think about is do to the bigger resistance of the intrinsic layer. The curve should look the same only the current will rise little bit slower, because...

Hi, I am working on a project where the normal process has been to push a single linear plain away from a given area. I am now considering lifting the single linear plain away but wondered about the physical dynamics when comparing pushing to lifting something. In the image:- A. Represents...

I've been reading about Quantum Field Theory. It strikes me that since the 1920's, physicists have changed the name "wave" to "field". I can't tell the difference between today's "fields" and what was described a "wave" in quantum theory in the early 1900's. So in quantum physics, is there a...

What is the difference between Constructive Proof of existence and Existential generalization? Logically they seem to be the same because, for a given predicate and specific member of the predicate's domain, you are concluding the general statement about the predicate.

I do know the difference between real and virtual images. I would like to know the difference between real and virtual objects. I need some examples. See this picture

Homework Statement For the solution to a given problem, in the second to last step I had: ##-\frac{\sqrt 6}{4} + \frac{\sqrt 2}{4}## I stated next that the solution was ##-\frac{\sqrt{6}+\sqrt{2}}{4}## I was told this was incorrect and that the correct solution is...

It seems to me that so far in quantum mechanics, because we have yet to establish probability patterns for, say, what the spin of a photon is, we have made it some mystical thing that we can only know by measuring it. I don't really buy that; is the result of a lottery impossible to know until...

Homework Statement In most problems involving projections I'm given a vector and the equation of a line either in parametric form or in symmetric form (ie. parametric: <0t+3, -t-4. 3t+2> or symmetric form: x=3, (y+4)/-1, (z-2)/3). However, when asked to use these in a problem I get confused...

Homework Statement In a TV tube, an electric potential difference accelerates electrons from a rest position towards a screen. Just before striking the screen, the electrons have a wavelength of 1.0 x10-11m. Find the electric potential difference.[/B] Homework Equations λ = h/mv Ek = qΔV The...

Hi, So I'm trying to self-study AP Physics C and found the first volume of Halliday/Resnick's Fundamentals of Physics on my parent's shelf, 3rd edition (from 1988). They also have the 2nd edition of University Physics, volume 2 (E&M). I do, however, have a copy online of the extended 10th...

Homework Statement A copper wire and an iron wire of equal length l and diameter d are joined, and a potential difference V is applied between the ends of the composite wire. Calculate the potential difference (in volts) across the iron wire. Assume that l = 2.00 m., d = 0.30 mm., and V = 156...

Homework Statement Two charges, A (-3 C) and B (+4 C), are placed 2.40 m apart. Point X is 30 cm from A, and Point Y is 30 cm from B. What is the electrical potential difference going from X to Y? Homework Equations W = △Vq The Attempt at a Solution Teacher gave answer as 6.9 x 10^4 V I am...

As per work energy principle, the energy spent in moving an object is stored as kinetic energy.Flow work is done to make the fluid move.Why is it not included in kinetic energy (i.e) why kinetic energy and flow work are considered seperately?

In my understanding, in group theory the one-dimensional irrep A differs from the one-dimensional irrep B in the symmetry under rotation about the principal axis: A is when the state is symmetric and B is when the state is antisymmetric under that rotation. However, I find in the character...

Hello, I'm struggling to understand how the electric potential difference is measure especially when a distance is not given. For instance in Serway, on the explanation of the Van de Graaff Generator the authora write, "Van de Graaff generators can produce potential differences as large as 20...

I know that the following two functions have the same derivative: ##\arctan (x-1)## and ##2 \arctan (x-1 + \sqrt{(x-1)^2+1})##. Out of curiosity, how can I find the constant value at which they differ? I tried to add ##\pi / 2## to arctan(x-1) but I'm not sure if that works or not...

Homework Statement Place 20.0 g NaOH(s) in a flask and dilute to 1.00 L with water. Place 20.0 g NaOH(s) in a flask and add 1.00 L of water. How exactly do these two statements differ? Wouldn't adding 1.00L of water to 20.0g of NaOH dilute it anyways? Homework Equations none? The Attempt...

Is there a difference between Schrodinger's equation and the wave function? In the beginning of the second edition by David J. Griffiths he compares the classical F(x,t) and Schrodinger's equation and I am having trouble understanding the connection.

I don't understand the difference between cast iron and high carbon steel. They both are an iron-carbon alloy and they both have a high amount of carbon within the iron metal. Both will oxidize at the same rate without a coating to protect the metal. Stainless steel will oxidize, it just takes...

http://oeis.org/A000088 This is a list that gives the number of simple graphs on n unlabeled vertices. Could someone conversant in graph theory explain why the number of simple graphs on 4 unlabeled vertices, which is 11, is the only one that seems to be odd (nontrivially), while the rest seem...

Homework Statement In a Newton's rings apparatus, find the phase difference (in radians) when an air wedge of 500nm thickness is illuminated with red light (lambda = 640nm). t = 500nm lambda = 640nm radians = degrees × pi / 180° Answer) 13 Homework Equations 2pi x path difference / lambda...

How come the gravity of a stellar- mass black hole is strong enough to trap light but the gravity of a stellar-mass star (eg the sun) is not strong enough to trap light ?

What is the difference between family of sets and indexed family of sets ??

Hi. I have been trying to solve this problem that has been keeping me up at night for a coupe weeks at least. If anyone can help me, I would be greatly appreciated. Hot air enters a cylindrical duct. The duct has some R-value and radiation and convection is being accounted for on the outside...

Hello, If two bodies, who say start with ##T_{cold}=T_c## and ##T_{hot}=T_h## and then they are brought in contact with one another and then after some time they both have the same temperature. What would be the entropy of the entire system? Also another quick question, I've looked at some...

Homework Statement If the electrons hit the tungsten target with an energy of 75 keV, find the potential difference. Homework EquationsThe Attempt at a Solution I tried this: (W=eV) V=W/Q V=eV/Q V=75,000/1.6*10-19 V= 4.6*1023 V, This seems wrong because all examples in my...

A star or a planet is a material object, while a black hole is an 'immaterial' spacetime object. Does the material or 'immaterial' nature of an object make any difference in how it curves or travels through spacetime as it manifests gravitation (apart from the powerful gravitation near a black...

What is the difference between the photon interaction mechanisms in emission due to absorption and reflection?

What is the exact difference between energy minimization and equilibration in a molecular dynamics simulation since both brings the system to the local energy minima?

Homework Statement All the bulbs in the circuits are identical, as are all the batteries. Rank the magnitude of the potential difference between points M and N. Homework Equations V=IR The Attempt at a Solution My most fundamental question is actually which way do I know to take the...

Kepler space mission has discovered thousands of exo-planet candidates. Why are they just candidates ? Why followup ground based study is required ? Why is Kepler unable to confirm them ? Second thing, how are scientists going to differentiate between eclipsing binaries mimicking to be exoplanets.

Information Given:In 1956, Frank Lloyd Wright proposed the construction of a mile-high building in Chicago. Suppose the building had been constructed. Question: Ignoring Earth's rotation, find the change in your weight if you were to ride an elevator from the street level, where you weigh 708...