All Questions
Tagged with electric-circuits work
33
questions
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54
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Do we have to provide energy to move electrons in an electric field?
In the positive and negative terminal of a battery, there is potential difference due to the accumulation of charges in their respective terminal, so it created a potential difference, and if we ...
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3
answers
169
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Why is Power in an electric circuit equal to $VI$? [closed]
Where did this formula come from? Everyone I asked just told me to substitute values of in ohms law to derive this but no one told why is power equal to voltage * current. Part of the reason for this ...
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2
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162
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What's the necessary work to increase the distance between two plates of a capacitor connected to a battery?
I'm trying to understand what happens, when the capacity of a capacitor connected to a battery changes.
I have this circuit formed by a battery that provides a potential difference of $\Delta V$ and a ...
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votes
5
answers
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Can we use work equation to derive Ohm's law?
Ohm's law states:
$$\textbf V=\textbf I\cdot\text R$$
where $\textbf V$ is voltage, the electric potential difference from a point to another (Electric potential is the potential energy of a positive ...
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2
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256
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Work-energy theorem giving no work done on capacitor and dielectric when dielectric removed from capacitor [closed]
For this problem,
Do you please know why when considering that the capacitor and dielectric is our system, the work energy theorem gives the wrong sign for the change in electrostatic potential ...
- 49
1
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2
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117
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Working of battery in circuit
The battery has a potential difference. So, shouldn't battery generate an electric field directing from the positive side to the negative side? If that's the case, we know that potential in a wire(...
- 1,179
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1
answer
99
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Work done by battery [closed]
In charging a capacitor to a charge $Q$
Is there an equivalent to this in setting up current through an inductive circuit?
Energy stored in inductor $= 1/2Li^2$
What would be the work done in setting ...
- 3
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10
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Why is Power = Voltage $\times$ Current?
So P = I*V because V is the amount of energy per coulomb and I is the amount of electrons going past a cross sectional area in one second.
So if we do the math, since V = J/C and I = C/sec, if we ...
- 191
2
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1
answer
164
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Does a CPU do work?
This question is simple to the Core (excuse the pun).
CPU = Central Processing Unit (for computing)
Lots of people including myself say "My CPU is doing a lot of work."
But I do not think ...
- 121
1
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2
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246
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What happens to electrons when they do work across a component in a circuit?
When a current flows through a component such as a lightbulb, how is work done?
I was thinking it was the speed of the electrons and that after a current goes through a lightbulb the electrons in the ...
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5
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What's the Difference Between Work and Energy? [duplicate]
I was trying to derive the formula $P = IV$, and I figured out to start from the basis that power is just work divided by time. In this case, I thought that I could use the formula $Vq = PE$ and ...
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Can someone please explain the work of a resistor?
Well I want to know what does a resistor do let our electrical appliances from burning in a circuit I know it does not slow the current flow so what does it really do?
- 11
2
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2
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505
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Sign of work done in an $L$-$R$ circuit
Suppose we have a L-R circuit with an inductor of inductance $L$ and resistance $R$ and emf $\epsilon$. Now initially when the switch is closed no current is present. Let the maximum current be $I_{...
- 159
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3
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184
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Neutral points in an electrical circuit?
I have been told that potential in an electric circuit is defined as the work done in bringing a unit test positive charge to that point inside the circuit. Thus it satisfies the premise that ...
3
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4
answers
379
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Voltage as work in electric field and in Ohm's law
I am struggling to reconcile the definition of voltage as work done moving a unit of electric charge between two points in an electric field and voltage in Ohm's law.
In the work definition, ...
- 155
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1
answer
214
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Energy stored in a capacitor vs Work that the battery does [duplicate]
Say we have a battery at a fixed voltage of $V$ charging a capacitor with capacitance $C$.
When the capacitor is fully charged, the energy stored in it will be $\frac{1}{2}QV$, where $V$ is the final ...
- 3,075
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120
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On work by a electric field in a electric circuit
If the electric circuit is complete, then one can say that the net average displacement of the electrons is $0$. Then consequently the work done by the electric field is also $0$.
So how is energy ...
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1
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243
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How does the battery do work on the electron although the speed of electrons is constant
In a simple circuit how does the battery do work on the electrons of the wire although their speed is constant .
Imagine I want to take a body which has 5 Newtons weight from the ground to 10 meters ...
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2
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3
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392
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Electric potential in circuits
From what I understand from my notes, an e.m.f or electromotive force provided by a battery is the electrical energy per unit charge converted from other forms of energy required to drive a unit ...
- 79
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0
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88
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Joule's heating effect
Can we derive joule heating effect or heating of current using energy conservation for electrons when current is varying with time ?Like using concept of drift velocity,potential diffrence across ...
user233089
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2
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326
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Work done by battery in moving charge $Q$ in circuit
why work done by a battery in circuit is potential diffrence across plates times charge flown through body.
W=Qε(ε is emf of battery)
although there are heat and other loses ? and another that my ...
user233089
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1
answer
368
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Work done in moving a charge in circuit?
Why is the work done in moving a charge from one point to another in a circuit through any path the same even though heat and other losses are there?
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Work done by battery?
Why the work done by a battery is Q*V where V is emf of battery and Q is charge that is made to flow in circuit?please explain detail?
explain and write the formulas
- 65
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485
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How do electrons gain energy in a cell?
When electrons reach the positive terminal, how does the cell do work on them?
I’ve read in a book that states voltage is literally the push that the cell exerts on electrons, which thus does work on ...
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How do voltmeters measure work done over a component?
In my physics class, we were shown the picture below to measure the current and potential difference through a component. We were told that the resistance of the ammeter is as low as possible, and the ...
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291
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Work done by electric field in a wire
Work done by electric field in moving a unit charge is the potential drop. In wires voltage (potential drop) is given by ohms law. Can somebody explain to me why work done by electric field can not be ...
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When talking about potential difference in a circuit, whose work done are we talking about?
I'm asking this because it seems to me that when we talk about PD around a charge (i.e. potential difference between infinity and a point), we're talking about the work done per unit charge by an ...
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441
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Work done on a battery
Consider a battery of EMF $E $ and label its positive terminal $P $ and Negative terminal $N $.
Consider current flowing through the battery from $N $ to $P $. Then work is done by the battery. This ...
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Work done by magnetic field on current carrying conductor
Suppose a wire of length L carrying a current I is kept in a uniform magnetic field B perpendicular to the current. The force on the wire will be IBL and work done by magnetic force when wire moves a ...
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What does electric potential mean in a circuit?
As we know that electric potential at a point is defined as a work done by me to carry unit charge from infinity to that point. How can I use this definition in an electric circuit that contains a ...
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