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Capacitors

A capacitor is a passive two-terminal electrical component used to store energy electrostatically in an electric field. By contrast, batteries store energy through chemical reactions. The forms of practical capacitors vary widely but all contain at least two electrical conductors separated by an insulator. For example, a common construction consists of metal foils separated by a thin layer of insulating film. Capacitors are widely used as parts of electrical circuits in electrical devices.

Where there is a voltage across the conductors, a static electric field develops across the insulator causing a positive charge to collect on one plate and negative charge on the other plate. Energy Is stored in the electrostatic field. An ideal capacitor is characterized by a single constant value called the capacitance. This is the ratio of the electric charge on each conductor to the potential difference between them. The SI unit of capacitance is a farad. It is equal to one coulomb per volt.

The capacitance is largest when there is a narrow separation between large areas of conductors. Therefore capacitor conductors are often referred to as plates. The insulation between the plates passes a small amount of leakage current and also has an electric field strength limit, the breakdown voltage.

Capacitors are often used in electronic circuits for blocking direct current while allowing alternating current to pass. In analog filter networks, capacitors smooth the output of the power supply. In resonant circuits, capacitors tune radios to particular frequencies. 

Estimating Power In An 8 Ohm Speaker

Estimate the power developed in the 8 Ω speaker of the circuit of the attached figure for a 1 kHz sinusoidal input signal of 100 mV peak. All capacitors may be assumed to act as a short circuit at the frequency of operation.

Circuit design

I have attached a cmos library for various transistors that pspice does not currently have. I only have access to the Q2N2222 BJT, CD4007 MOS transistor and the 2n7000 transistor and of course all the various resistors and capacitors. If you could please help me design a circuit with the attached specifications using only the pa

Electricity, Magnetism and Waves

See the attached file. 3.) A head is (approximately) a conducting sphere of radius 10 cm. What is the capacitance of the head? What will be the charge on the head if, by means of a Van De Graaf generator, you raise the potential on the head to 100,000 V? What voltage would be required to cause electrostatic break down in ai

Amplifier Design: Schematic diagram, Theory of operation, SPICE simulation

The Applied Magnetics Laboratory at the university is developing imaging techniques for monitoring drug delivery to tumors with nano-sized magnetic beads. For this project it has been determined that an amplifier with the following specifications is needed: i) Open circuit voltage gain in |Vo/Vin| of 300 +- 10%. ii) Input re

Calculate: AM, SSB Reception and Modulation

1. You are asked to build an AM receiver with a 15 micro H inductor which must tune from 500 to 880 kHz. Find the required variable capacitance and the bandwidth at 770 kHz, if the ideal bandwidth at 380 kHz is 10 kHz. 2.A receiver tunes from 20 to 30 MHz using a 10.7 MHz IF. What is the range of the oscillator and image fre

Dielectrics and Infinite Electric Cylinders

1. The space between the spaces of a parallel plate capacitor is filled with two slabs of linear dielectric material. The slabs have different dielectric constants but the same length L, width W and thickness d. (note the area of the top (or bottom) of the capacitor is 2*L*W). Slab 1 has a dielectric constant of e1=2 and slab 2

Capacitors in series and parallel

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A fuel gauge uses a capacitor to determine the height of the fuel in a tank. It measures the dielectric constant of the combined air and fuel between the capacitor plates as a function of fuel level. To derive an expression for effective dielectric constant etc..

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5 questions to understand capacitors in series.

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Two problems on capacitors

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Calculating Capacitance

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A parallel plate capacitor with a nonuniform dielectric

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Consider the following parallel plate capacitor Givens: top plate 1 meter wide by 1 meter deep by 10 mm thick bottom plate 1 meter wide by 1 meter deep by 10 mm thick gap 12 mm applied voltage 1000 volts containing different materials inside the gap as follows: a) 12 mm of vacuum (Ke = 1) b) 1 mm of vacuum, 10 mm of

Charge on the capacitors when reconnected oppositively.

Two capacitors, with capacitance 4.20*10^-6 F and 5.90*10^-6 F, are connected in parallel across a 660-V supply line. The charged capacitors are disconnected from the line and from each other, and then reconnected to each other with terminals of unlike sign together. a) find the final charge on the 4.20*10^-6 F capacit

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Based on the assigned scenario, answer the following questions: What is the situation? What challenges exist? What opportunities exist? What is the problem? Is there a problem? Is it worth solving? (Process) Based on the assigned scenario, answer the following questions: What does the ideal end-state look like? What are the

Capacitor Question

Please help with the following problem. Provide step by step calculations. A capacitor, C1, is charged using a 6.3 V battery. C1 has a capacitance of 3.55μF 1) When this capacitor/battery circuit reaches equilibrium, what is the charge on each place of the capacitor? 2) When C1 is fully charged, the battery is remove

A parallel plate capacitor with plates of area A and plate separation

A parallel plate capacitor with plates of area A and plate separation d has the region between the plates filled with two dielectric materials (ε1 and ε2) as shown in the figure. Determine the capacitance and show that when ε1= ε2= ε your result becomes the same as that for a capacitor containing a singl

Complex coupled circuits

The circuit configuration chosen is that of a pair of tuned circuits which are coupled together and both primary and secondary are tuned to the same frequency. The primary has an inductance of 1 mH and the secondary has an inductance of 1.5 mH. The resistance of the primary is 10 ohms and the secondary 12 ohms. the secondary is

Connecting Three Capacitors

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Electrostatics: Coulomb's law, polarization, capacitance.

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What is the equivalent capacitance of the two capacitors

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Capacitors

Consider a group of capacitors, where C1=14 µF and C2=6.8 µF. Terminals A and B are connected to a 9.0 V battery. Find the energy stored in each capacitor. 14 µF capacitor : 6.8 µF capacitor : 22 µF capacitor: Please see attached for diagram.

Potential Between Different Dielectric

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Define Non-Destructive Testing and Non-Mechanical Properties

Please provide assistance with the following: Section 2 Define what is non destructive testing and illustrate some of it's usage. to support this detail three methods of non destructive testing and write a clear explanation of the process involved and where they might be used. Section 3 Choose one of the following areas and

What is the equivalent resistance and capacitance?

1. A 100 ohm resistor is joined in parallel with a 47 ohm resistor. What is the equivalent resistance? 2. Three capacitors of 2.0, 5.0, and 20 microF are joing together in parallel. What is their equaivalent capacitance? 3. Three capacitors of 1.0, 1.5, and 5.0 uF are joined together in series. What is their equivalent cap

Capacitors

Two capacitors are connected in parallel. If a third capacitor is connected in parallel with the other two, does the equivalent capacitance increase, decrease, or remain the same? Explain.

Voltage on a capacitor

A 12.5 micro Farad capacitor is charged by a 150 volt battery and then is disconnected from the battery. When this capacitor (C1) is then connected to a second (uncharged) capacitor, the voltage on C1 drops to 10 volts. What is the value of C2? (I need a very detailed solution, with every micro-step detailed)