Source Definition and 1000 Threads

I am familiar with the concept of the internal resistance of a voltage source, but what is meant by the input impedance?

Attached is the model. Find Vx and Vy. The Attempt at a Solution The total resistance is 10 ohms, and the circuit elements are all in series. So 2 Amps of current is flowing in the direction of the arrow in the diagram across all elements, Vtotalsrc = (to the voltage from the current...

Is dark flow evidence of other universes?

Hello again, I am having a bit of trouble understanding superimposed voltage. Here is the problem: A sinusoidal AC voltage source is in series with a DC source. Effectively, the two voltages are superimposed. Draw the total voltage across RL. Determine the maximum current through RL and the...

if lasers produce so much power why can't we use it as an energy source

Imagine this, there are 2 light source (laser perhaps) pointing each other with a distance between them. They have the same frequency, wavelength and amplitude. But, laser 1 start with positive amplitude while the laser 2 start with negative amplitude (start off from negative), what would happen...

Homework Statement A certain practical dc voltage source can provide a current of 10.5 A when it is (momentarily) short- circuited, and can provide of 30 W to a 20 Ω load. Find the open-circuit voltage Homework Equations V=IR The Attempt at a Solution Well I'm pretty sure that...

I am designing a machine to produce electricity , using pressure as a source of energy. So my question is simple, is there any machine or device that are used to produce electricity from pressure?

Classically as well as quantum-mechanically, the source of the Maxwell field is the electron/four-current (Dirac field), so the use of the Green Function propagator for the Maxwell field makes perfect sense: the Maxwell field is inhomogenous in the presence of matter. But what about the source...

Hi guys, I'm trying to compile an open source program (chess and chess variant engine) under linux but for some reason it doesn't work. I know almost nothing regarding programming so I don't know how to fix the problem. In a chess server I asked some programmers if they knew how to fix the...

Hi All, Thanks again to all the great mentors and contributors to this forum. I wanted to ask a question about the Gauss's law/Ampere's law equations in Maxwell's Equations: \nabla \bullet \textbf{E} = \frac{\rho}{\epsilon_0} \\ \\ \nabla \times \textbf{B} = \mu \left( \textbf{J} + \epsilon...

Hi everyone, I have attached an image of fet amplifier in common source configuration. I want to have the ac analysis of this circuit. I am able to figure out the input impedance and the voltage gain. But I can't formulate for output impedance. According to me, while calculating output...

hi i just want to ask about the formula of Doppler Effect . The speeds of the listener VL and the source Vs are relative to the ground, source, or listener ?

This is something I don't relly get. I keep reading that the intensity of a wave is proportional to the square of its amplitude. So let's suppose we have a random wave source, with amplitude A0. If we replace that source with five identical copies of it, their collective amplitude is 5A, yes...

what is the source of the first photon in the laser ? i understand there is a burst of light or electricity that excites up the medium , but what is the source of the first photon ? is it the light source or is it one atom of the medium itself releasing photon as it gets de-excited * if...

mcnp error "the new source has overrun the old source" I am a beginner with MCNP. This error really confused me. Who knows what this error means? Thank you.

Hi all, I'd like to solve the following problem in 3 dimensions: \partial_t u(r,t) = D\Delta u(r,t) u(r,0) = 0 u(0,t) = C_o In words, I am looking at a point 'source' that is turned on at t=0 and held at constant temperature. The ultimate goal is to then convolve this solution with...

We know that the conservation of electromagnetic energy is expressed via the continuity equation below: \large{\frac{\partial u}{\partial t}}+\vec{\nabla}\cdot\vec{S}=-\vec{J}\cdot\vec{E} with u=\frac{1}{2}(\vec{E}\cdot\vec{D}+\vec{B}\cdot\vec{H}) and \vec{S}=\vec{E}\times\vec{H} . It...

What is the equation to find relative sound intensity from a source when given the angle?

An object is an isotropic light emitting source and the object moves very near the speed of light c. I am an observer on a planet without an atmosphere and I see the path of the object as a line that is perpendicular to the normal from the planet's surface where I am standing. Now take a line...

So.. I'm a biomedical engineer, and a new technology that is arising is being able to control magnets that "swim" around the body using electromagnets oriented around the outside of the patients body. It has been said that electromagnets can't be used on the inside of the patient because they...

I have very little knowledge of physics so the simpler you can keep your replies the better for me. Newton put forth a gravity theory that essentially said that there is a force that pulls on us to keep people on the Earth and this is gravity. Einstein came along and included in his theory...

Homework Statement "How could you show that a radioactive source was only emitting alpha and gamma radiation?"The attempt at a solution This really stumped me...obviously they have different penetration distances, and different strengths of ionisation, but I don't know how to show that only...

I'm looking at an AC circuit. There is a voltage source, a resistor, an inductor, then another voltage source. One loop. I am supposed to find the power in each element and tell weather it is absorbing or delivering. I think I remember that when a current goes into the negative terminal of a...

Lithium Hydride contains more hydrogen per unit volume than liquid hydrogen does, so what is stopping us from developing a Lithium Hydride storage solution to supply hydrogen to a vehicle's engine? The reactivity of the substance would throw up some substantial challenges, but compared to...

Apologies for what may be a basic question, I am unfamiliar with RF systems but much more familiar with optics. I need to connect some standard coax to some microcoax; they do not have exactly matching impedances so there are reflections. It seems to me I should be able to make an...

I'm looking for a good text or online source that can take me through radiometry at an undergraduate level. I'm interested in drill type problems that can help me sort out the different quantities intensity, irradiance, exitance, radiance and their spectral counterparts. Also, solid angle vs...

Let's say I have an indestructible speaker and I launch it out of a cannon at Mach 1.5 while it's playing music. (To make things simple, it also has an iPod and battery attached to it.) If the speaker passes a stationary observer, will they hear each cycle of the sound wave from the speaker in...

So I have a bit of a story here. First of all, I work in my university's radiation safety department, where, among other things, I calibrate Geiger Counters. I also passed Modern Physics (Physics III), so I got some education on radioactive decay. I have an old Counter from 1962, a...

Homework Statement Here's the problem: Find the equivalent conductance Geq and then the equivalent resistance Req "seen" by the current source Is in the circuit in terms of the literals R1, R2, and gm. Figure: Homework Equations Ohm's Law: V = IR KVL: V1 + V2 + ... Vn = 0...

Homework Statement calculate the power consumed by dependent source Homework EquationsThe Attempt at a Solution The 10A source does not build a supermesh. Loop 3: (i3-i2).(1/10)=0 => i3=i2 Loop 2 : i2=10(A) i3=10(A) vx.(10)=10=> vx=1(V) (node voltage) also for loop 2 ...

Homework Statement What is the photon flux (photons/ m2 s) at a distance of 1 km from a light source emitting 50W of radiation in the visible domain, with wavelength 6000 Angstroms. Homework Equations The Attempt at a Solution Energy of one photon = hc/λ = 3.32 x 10-19J. So, number...

If we have a circuit (see attached) will our voltage source's supplied voltage be delayed by the capacitor in anyway? (as the voltage across a capacitor lags the current through a capacitor by 90 degrees) then, as the resistor,voltage source, and capacitor are all in parallel does this cause the...

Homework Statement Homework Equations The Attempt at a Solution

Homework Statement I am a bit confused on why they can just randomly short the 4kΩ resistor, as you can see from the first pic to the second pic. THanks Homework Equations The Attempt at a Solution

Homework Statement Use source transformation to find the Thevenin equivalent circuit with respect to terminals, a, b. Homework Equations Voltage Division: (V in)*(R1/R1+R2) Thevenin / Norton / source transformation procedures RTh = RNo VTh = INo*RNo Polar...

Hi! I was doing some exercises about the doppler effect on sound until I found this problem that I can't find the solution! "A source of sound of frequency f0 moves horizontally at constant speed u in the x direction at a distance h above the ground. An observer is situated on the ground at...

In the full wave centre tap rectifier, piv of diode require is twice of the input current of the transformer. I can't understand why is it twice when the source is only 1V-peak.

Hello Dear Fellows! We all know that light is an electromagnetic wave and also we know that an antenna receives EM waves and convert it into electrical energy. My question is that is it possible for any specially design antenna to receive Light as a source of EM waves...

Homework Statement Find Vout at t=0.782s (I already found Vout at t=0 s. It is 0 V.) Homework Equations V=IRThe Attempt at a Solution First I found Vs = 9*sin(14*0.782)=-8.989817V (with t in radians) Since Rpi is in parallel with the Vs, its voltage Vpi also equals to -8.98917 V. Since the...

Homework Statement R=50Ω L=5H C=1/125F vs=200.[1+u(t)] V Find i(t) Homework Equations The Attempt at a Solution Write the KCL equation -vs+Ri+L.i'+1/C.∫idt=0 Do the derivation to get rid of the integral, replace all possibly values, we got: i''+10i'+25i=1/5.vs' (*) solve...

Is the laser perfect monochromatic light source?

Homework Statement 2 point sources 20cm apart produce 3 cm waves at a rate of 8 waves every 1.2 secondsHomework Equations how many nodal lines are present what is the angular deviation of the 3rd nodal line? what is the angle between the 3rd nodal line and the 5th nodal line? The Attempt at a...

I do not know how to approach this. I am trying to use r1 - r2 = mλ but I can't seem to find the answer! please help. I figured it out that it is constructive, but i just don't know how to mathematically prove it. r1 - r2 = mλ.

Hi, I currently have a black body calibration source which I use for work. It works great, I can calibrate all the IR thermometers just fine, however it isn't a simple quick "check". The IR thermometers are the ratio type in that they measure two wavelengths and using the ratio it can work out...

Homework Statement Solve for the flux distribution using the 1D neutron diffusion equation in a finite sphere for a uniformly distributed source emitting S0 neutrons/cc-sec. My problem right now is that I can't figure out the boundary conditions for this problem. We usually work with...

My company uses MS TFS for source controlling and I find this really difficult because we have to code on VMs (log on VMs and handle the code in TFS). I would like to make a suggestion to change this into SVN using command line or Tortoise GUI tools. But the client seems not to let publicly seen...

Homework Statement determine thevenin equivalent of circuit at terminals (a,b): Homework Equations Z(L)=jwL Z(C)=-j/wC V(th)=V(oc) R(th)=V(ex)/I(ex) The Attempt at a Solution actually 1st i need help with finding V(th). i do know that V(th) would be the voltage across the 2ohm resistor, so...

Hi I want to define an Am-Be source in MCNPX 2.6 I have Neutron spectrum But I don't have Gamma spectrum of this source. Please Help!

I know that the quasar is a huge source of energy, it can produce energy and light more that glaxies do ; so the question is how that can be possible and the quasar is a super massive Black hole which absorb every thing even Light couldn't escape ?! My Friend tell me when the Black Hole is...