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20

If electric signals are the propagation of EM waves at close to c in which direction do these waves travel? In the conventional direction? In the direction of electron flow? In both directions? "Both" directions, as well as an omnidirectional component. The best example might be an Ethernet cable. A bit is represented as a pulse. To transmit this ...


11

signals travel in all directions like waves in a pond, they are a disturbance in the current not necessarily a current themselves.


7

The differential equations which use \$\frac{di}{dt}\$ and \$\frac{dV}{dt}\$ are more fundamental. They do not do not care about any abstractions such as "frequency", "sinusoids", or "canned" waveforms which, in a sense, need you to know what is going to happen in the future. As a result, you can always use the differential ...


5

Those words which are used to describe statistical distributions - how they differ from the Gaussian bell curve - are not common when one wants to describe with words how a pulse looks in an oscilloscope. That's because elecric circuits can have even much more complex forms of voltages vs. time, there's no "normal pulse form". If you have a noise ...


4

I believe the vertical bars inside the integration denote magnitude. This exponent is a phasor whose magnitude is one and angle is (wt). The square of one is also one. The magnitude of the phasor (or complex number) is the square root of: the real part squared plus the imaginary part (without j) squared. When you add sin^2 and cos^2, the result is one. Hope ...


4

Notice, that \$\forall x\in\mathbb{R}\$: $$\left|\exp\left(xi\right)\right|=1\tag1$$ Because: $$\left|\exp\left(xi\right)\right|=\left|\cos\left(x\right)+\sin\left(x\right)i\right|=\sqrt{\underbrace{\cos^2\left(x\right)+\sin^2\left(x\right)}_{=\space 1}}=\sqrt{1}=1\tag2$$ So, for your integral we get: $$\int_0^{\text{T}_0}\left|\exp\left(\omega_0t\text{j}\...


4

That depends very highly on the specific conditions or application you look at. I don't know of any general rule of how to interpret these statistical parameters in regard to electrical measurements, you really need context to do this. I can only give you one example from my area of work: When you measure the sEMG (very small voltages on the surface of your ...


4

The signal in a cable is carried by a radiowave which propagates in the space around the wires. Parallel wires or twisted pair have this capability. Coaxial cable also has it, but the wave is limited to the insulation layer between the middle wire and the shield. The wave happens as electric and magnetic fields, it's not inside the metal. The electrons in ...


3

My question is, do these formulas always hold? Apart from the physical limit cases when transmission line theory take over, the formulas always hold irrespective of waveform shape: - $$I = C\cdot \dfrac{dv}{dt}$$ $$V = L\cdot\dfrac{di}{dt}$$


2

According to Maxwell's laws, there are 2 types of electrical signals: 1 - Conduction current signals The energy of the signal is proportional to the overall kinetic energy of all electrons moving in a host material like Copper or Silicon. 2 - Displacement current signals The energy of the signal is proportional to the overall electrical and magnetic energy (...


2

This answer on how the electric field is established in a DC circuit might help you visualize what happens in the initial moments in your imagined circuit. When you close the switch, surface charge that had accumulated at the switch's terminal will start to recombine and redistribute in order to establish the uniform electric field \$E = j/\sigma\$ directed ...


2

According to the op amp's datasheet, with +/-15 V supplies (i.e. 30 V between the supply pins) the input common mode range is only In other words, your input cannot rise to within about 0.5 V of the positive supply nor fall to within about 3.5 V of the negative supply. Performance is even worse over temperature -- e.g. your input cannot be within 2 V of the ...


2

There are a few notable clues in the data sheet that this op-amp will not work from a single rail supply of ground and + 5volts: - The graph above tells you that the minimum supply voltage is +/-5 volts or a single rail of ground and +10 volts. Do you see the problem: - Then there is the input common mode voltage range: - What this is telling you is that ...


2

The AD713JNZ requires a double-ended power supply. That means you must power it with +V and -V. Try powering the -V pin with -5V or switch to a single-ended opamp.


2

I'm being very handwavy, but... Interpreting the skewness or kurtosis of a distribution isn't actually so straight-forward, even in the setting of plain old probability theory. What you need to realize is that these "higher-order moments" are "just" (i.e., modulo some details, scaling, etc) the coefficients of the Maclaurin expansion of ...


1

Yes, in the sense that the magic therapy thing is BNC and specifies a frequency range that the synthesizer is capable of producing.


1

My question is, do these formulas always hold? The answer is really "yes" and "no". Other answers have explained the "yes" answer, but they all depend upon a capacitor or inductor being "ideal". Real capacitors and inductors have "stray reactances" and resistances. But even if we ignore these, real ...


1

The impedance formulae always hold true (within specs) but the spectrum of the input signals can be varied from sinusoidal so the response depends on the circuit transfer function. s domain plots or Smith charts or Bode amplitude and phase plots will demonstrate this.


1

Just thought I'd chuck in that the average speed of the electrons flowing through a copper wire due to the electric field is only about 1 mile per hour - but they effectively push each other along. Signals don't propagate at the speed of light in a vacuum (i.e. c = 300,000,000 m/s) of course. If you're thinking about optical fibres then the light particles (...


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