Capacitance Definition and 874 Threads

Homework Statement There exists a potential difference V between the plates of a parallel plate capacitor of capacitance C. Now it is connected to a cell with potential V. What will be the heat generated? Homework Equations Work(on battery) - (energy stored in Capacitor) = Heat produced The...

Homework Statement I calculated the capacitance of two concentric conducting spherical shells of radii a and b (a<b) when the inner shell has charge Q and outer has charge -Q correctly by using C=Q/(V(i)-V(o)), the problem I have is described below in "attempt at a solution" Homework...

I have an outer cylinder and an inner cylinder given. They are hollow(like if you were to take a sheet of paper and tape one edge to the other), grounded, and the inner cylinder is inside the outer cylinder. Between these cylinders is an ungrounded cylinder. I am now asked to calculate the...

I have been researching on the bonding energies of different compounds, and for example, for CO2 it is 1600kJ/mole, 1600kJ/44g, or ~36.37kJ/g of energy required to split the carbon dioxide into carbon and oxygen. Furthermore, I transformed the amount of energy required in kJ to degrees celsius...

Homework Statement Assume a conducting sphere has a radius of 3400km with an electric field of 100 V/m at it's surface. a) Calculate total charge of sphere. b)Calculate potential at the surface using infinity at reference point c) Calculate capacitance of the sphere using the result of a or b...

The picture attached with this post shows a combination of capacitors, we are asked to find out the equivalent capacitance between the points A and B. Provided that all the capacitors are identical and has an individual capacitance C. Can anyone help me provide basic ideas of solving these kind...

Homework Statement Homework EquationsThe Attempt at a Solution I think the circuit given above is incorrect due to the presence of the two resistors . I have never seen/done a problem where equivalent capacitance is to be calculated across two points in a circuit , having resistors along...

Homework Statement Hi there! So I have found trouble with the following problem. I have a system of two eccentric spheres, where one is inside another. The Attempt at a Solution I have found this answer: https://physics.stackexchange.com/questions/16939/capacitance-of-non-concentric-spheres...

I have done an experimeny to investigate how the voltage across a capacitor, Vc varies as it charges and to find the capacitive time constant in a DC RC circuits and Study resonance in an AC inductor-capacitor circuit (AC LRC circuit). I am now having trouble in writing the source of error of...

Homework Statement Two parallel-plate capacitors with the same plate separation but different capacitance are connected in parallel to a battery. Both capacitors are filled with air. The quantity that is NOT the same for both capacitors when they are fully charged is: A. potential difference...

Homework Statement A battery is used to charge a parallel-plate capacitor, after which it is disconnected. Then the plates are pulled apart to twice their original separation. This process will double the: A. capacitance B. surface charge density on each plate C. stored energy D. electric...

Homework Statement [/B] The figure [attached] below shows a variable "air gap" capacitor for manual tuning. Alternate plates are connected together; one group of plates is fixed in position, and the other group is capable of rotation. Consider a capacitor of n = 4 plates of alternating...

Homework Statement I have to rearrange the equation V=lnVo -t/RC to calculate C. The gradient from graph = -1/RC Homework EquationsThe Attempt at a Solution I got R/C=ln(Vo-V)/t but the answer I get is wrong

Is the equation used to determine the density of interface states in schottky diodes from capacitance- frequency data applicable to PIN junctions?

Homework Statement Homework EquationsThe Attempt at a Solution First I calculated equivalent capacitance between R and M . The two 2μF capacitors are in series . Their combination is in parallel with the 1μF capacitor . Their equivalent capacitance is 2μF . Now I found equivalent...

Good day, everyone. Let's picture a classic diagram of a voltage booster which is connected to a capacitor. If we double the capacitance, by replacing it using another capacitor with the same voltage rating as the previous one, will the circuit still be able to charge the new capacitor up to the...

I'm having a little trouble understanding capacitors in parallel and series. I understand that if there are two capacitors in a circuit with a potential difference Vab then the potential difference across the capacitors is also Vab. Every example I have seen have been for two capacitors with...

Homework Statement The capacitor (of thickness d) is disconnected from a potential source of V and a dielectric of thickness t is inserted and it has relative permitivity Er. Find the new potential between the plates Homework Equations [/B] This is the answer : Vf = V/d(d - t + t/Er) The...

Homework Statement Find the energy in the 2uf capacitor in the diagram attached in uploads. Homework Equations E=(1/2)CV^2 E=QV C=Q/V Capacitor in series : 1/(Equivalent Capacitor) =Σ1/(Ci)* Capacitor in parallel: Equivalent Capacitor =∑Ci* *i is the index of summationThe Attempt at a Solution...

If given a capacitor with stored charge, would its charge remain constant before and after it is immersed in a liquid (i.e. distilled water)? Why? I know that before immersion, the capacitance would be = (ɛAV/d), but would that be the same if immerged in distilled water?

Homework Statement w = 1 rad/s power factor is 0.8 lag Homework Equations Using Phasor we can do The Attempt at a Solution Since pf = 0.8 lag. I source lags V source by 36.87 degrees. Vc is voltage across Capacitor = Voltage across ( Resistor + inductor) Solving this I get C = 0.5 But book...

Hello, I'm having the damnedest time wrapping my head around a concept of audio electronics: http://whirlwindusa.com/support/tech-articles/high-and-low-impedance-signals/ How exactly does a higher impedance bring down the frequency at which capacitance dominates? My current understanding is...

Homework Statement There is a charged particle at height h over a circular area of radii R, then I have to calculate the capacitance. This is useful when somebody want to calculate energy harvesting, antennas, sensors that measures ions in plasma devices and particle accelerators...

Homework Statement A single phase transmission line has 2 parallel conductors 1.5 metres apart. The diameter of each conductor being 0.5 cm. Calculate the line to neutral capacitance for a line 80 km long[/B]Homework Equations CAN = 2(3.14)(permittivity)/Loge [D/r] This gives capacitance per...

Ok, so I am am trying to make a homemade capacitor that is 4700pf and 15kv. polyester at 125 micrometers thick can withstand 15kv so were good. here is the equation i used C=ε0 K A / D Where C = capacitance, ε0 is epsilons constant, K = dielectric constant, A = area of aluminum foil, and D is...

The capacitance formula for equal line is as follows. : * my question : I want to know the capacitance formula for unequal lines and its solving process . Thanks in advance for any hint.

Homework Statement the capacitance of each capacitors and the cell voltage Homework EquationsThe Attempt at a Solution I got the total capacitance = 8028/5333 uF total voltage = 36v total charge=289008/5333 uC

Hey everyone, I'm trying to measure the stray capacitance in a circuit comprised of an rf signal generator, an oscilloscope, a coaxial cable (short-circuited) and some capacitors. I measured the resonant frequencies of the coaxil cable for varying values of capacity (0pF to 850pF) between 4MHz...

I understand algebraically that when capacitors are in series, the total capacitance is less than any individual capacitance, but I do not understand this intuitively. How can this be possible? Shouldn't more capacitors equal more capacitance?

Does an increase in Capacitance mean a decrease in voltage? Thanks!

Consider a parallel plate capacitor formed by two plates of length ##L## and width ##d##, separated by a distance ##e##. There is a vacuum in between the plates. Let's note the capacitance of this arrangement ##C_0##. I insert a conducting plate of length ##l=L/2##, with ##D##, and thickness...

Dear all, I am trying to find the capacitance of a parallel plate structure that comprises a spatially varying (linear) dielectric in one dimension. I have two methods of solving this which give different answers, and I am not sure which is correct. I consider the dielectric region to be...

Homework Statement How long does it take in time constants ( = RC) for the charge on the capacitor in the circuit shown below to reach one quarter its initial value? Homework Equations C=Q/V time constant=RC Vc = Vo * (e)^(-t/RC) The Attempt at a Solution From C=Q/V I get Q=VC so for the...

Hello, Let's consider a capacitor simply made of two conductors with arbitrary shape in the vacuum (http://www.kshitij-iitjee.com/Study/Physics/Part4/Chapter26/3.jpg). Now, if I place a small piece of dielectric material (for example a tiny sphere of glass) between the two conductors, the...

Can someone point me to an understanding of why VFD rated cable include Inductance and Capacitance? For example, Belden cable 29504 shows impedance, inductance, capacitance between conductors, capacitance between conductor and sheild, and DC resistance. Is there a VFD motor calculation that is...

Homework Statement Consider a disc (negligible thickness) of radius R with its center at the origin. Assume that the disc has a radially symmetric surface charge density given by ##σ(s) = \frac{A}{\sqrt{R^2-s^2}}## at a distance s from the origin, where A is some constant. You can take it for...

Homework Statement The output voltage, V_(out) (t) ‡ q(t) /C, effectively measures the charge on the capacitor as a function of time, where q(t) is an exponentially damped simple-harmonic oscillation: a) Given that L = 0.05 mH, the square-wave frequency is 25kHz, and the ringing decays to 40%...

Homework Statement 1. An RC filter is constructed by modifying a voltage divider. The top resistor R1 = 3kOhms remains the same but the bottom resistor R2 is replaced by a capacitor C = 8nFarads. Determine the corner frequency fc for this filter in kHertz. 2. For an RLC circuit R = 12.4...

This question is from my physics book and neither I nor my teacher can find the mistake in my method. (The original question is not in English so I'll do my best translating it) > When a coffee maker is connected to the wall (230 V, 50 Hz) its power consumption is 180 W. The power consumption...

Homework Statement [/B] Hey everyone, I recently got two problems on capacitance and inductance and need some help on them. Here are the two problems: 1. A Royal Red Robin Burger contains 1230 food calories. Also, more that the daily requirement for protein, fat, sodium ..., even without fries...

Homework Statement The circuit in Fig. 32-31 consists of switch S, a 12.0 V ideal battery, a 20.0 M resistor, and an air-filled capacitor. The capacitor has parallel circular plates of radius 5.00 cm, separated by 3.00mm. At time t=0, switch S is closed to begin charging the capacitor. The...

Homework Statement A Sheet of conductor of thickness t and parallel faces of cross-sectional area >=A is inserted between the plates of the capacitor of a parallel plate conductor. Show that the capacitance increased by ΔC= ε0tA/d(d-t) Homework Equations σ,ε0,Δ The Attempt at a Solution...

Homework Statement You charge a parallel-plate capacitor, remove it from the battery, and prevent the wires connected to the plates from touching each other. When you pull the plates apart to a larger separation, do the following quantities increase, decrease, or stay the same? (a) C (b) Q...

Homework Statement [/B]Homework EquationsThe Attempt at a Solution I really have no idea how to proceed. Applying Kirchoff's laws to this would be quite lengthy. This circuit is supposed to be a wheatstone bridge but I can't see it.

As distance between two capacitor plates decreases, capacitance increases - given that the dielectric and area of the capacitor plates remain the same. So, why does this occur?

What are the effects of adding inductance and capacitance as secondary load of transformer? I am using a Ring /Toroid Transformer.

Homework Statement The plates of an air filled parallel plate capacitor with a plate area of .0016 m^2 and a separation of .009 m are charged to a 145 V potential difference. After the plates are disconnected from the source, a porcelain dialectric with k = 6.5 is inserted between the plates of...

Homework Statement Three capacitors are connected in series, C1 = 4.5 mF, C2 = 7.5 mF, and C3 = 10 mF, and connected to a 150V d.c. supply. Calculate: (a) the total capacitance...

I have a hard time comprehending excess charge in capacitor plates. Let's say we have two identical capacitor and we charged them to identical amount of charge. Next we connect them in series by opposite sign electrodes and we get double the voltage on the open ends. Now a single capacitor has...

Homework Statement I would like to know how to calculate the total capacity of the capacity network displayed in the uploaded picture. I know how to calculate the total capacity if the capacity are in parallel or in series, but I am confused by the capacity Nr 6. I know how to calculate the...