All Questions
Tagged with electromagnetic-induction electrical-resistance
41
questions
2
votes
2
answers
116
views
Confusion related to emf in a loop
To calculate the current in a closed loop of resistance R subject to a changing magnetic field which generates an emf $ \epsilon= - \frac {d(\phi)} {dt} $, we use the relation ohm's law in the form.
$\...
- 292
0
votes
2
answers
119
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Why current does not instantly reach maximum value in an $LR$ circuit?
In an $LR$ circuit, I read that when an resistor $R$ and an Inductor $L$ are connected to an emf $E$ source in series, and the switch is switched on, the current flowing in the circuit does not ...
0
votes
1
answer
81
views
How do non-ideal inductors behave in a circuit?
I cannot comprehend how
can we break a seemingly non-ideal choke coil into just a pure resistor and inductor in series according to the following solution of a question.
Considering the data in the ...
- 5
0
votes
2
answers
49
views
$I²R$ loss in case of transformer
Suppose we have a 100 V A.C. supply, and we connect a 1 ohm resistor with it. Now the current through the resistor will be 100 A. Now we connect a 1:2 step up transformer with the A.C supply, and then ...
- 11
1
vote
0
answers
42
views
Is my reasoning about $ε = iR$ correct, where $ε$ denotes induced emf, $i$ denotes induced current, and $R$ is resistance of loop [closed]
I came up with the formula, $ε = iR$, where $ε$, $i$ and $R$ denotes induced emf, induced current and resistance of loop respectively. I did the following reasoning to prove this formula, am i right?
- 19
1
vote
1
answer
90
views
Validity of Ohm's Law due to Induced Electric
If we have a conducting loop of resistance R in a region of varying external magnetic field, how can we determine the current through the loop?
First, if we consider Ohm's Law, then we get that
$$\...
- 301
1
vote
3
answers
128
views
$RL$ Circuit Initial Condition - Why is $I$ continuous?
In a simple $RL$ circuit with a switch, the switch is closed at $t = 0$. Then the differential equation we are solving is $V_0 -L \frac{dI}{dt} = IR_0$, and the solution is $I(t)=\frac{V_0}{R_0}+ke^{-\...
- 171
1
vote
3
answers
97
views
Understanding voltage in AC
With DC, for example, a battery, it's easy to understand that one terminal is more negatively charged then the other, so that there is a potential difference between the terminals, which creates a ...
- 282
1
vote
1
answer
253
views
Does the electric field ($E$ caused by induction) of a moving conductor in a magnetic field drop when connected to a curcuit?
We know that when a conductor moves in a homogenous magnetic field that is perpendicular to itself due to the amount of electric charge gathered on one end of the conductor( as a result of the lorentz ...
1
vote
1
answer
228
views
Current when inductors charging in parallel are discharged in series
We started discussing DC RL-circuits in class and were analyzing the following circuit
The scenario is the switch has been closed for a long time so the current through both 2-ohm resistors is the ...
- 11
0
votes
1
answer
99
views
In a LR circuit, Why do the current rate of increase decreases with time? [closed]
In a LR circuit, the current rate of increase decreases with time until it reaches zero eventually and that is when the current become steady. My question is why the current rate of increase decreases ...
- 959
1
vote
2
answers
308
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Regarding Lenz's Law presented in hyperphycsics
The following diagram is presented in hyperphysics as an introduction of Faraday's Law and Lenz's Law.
If the red arrows represent the direction of current, then what do the positive and negative ...
0
votes
1
answer
147
views
What effects do inductors have on circuits?
The above diagram is a simple circuit containing an inductor.
According to the right hand grip rule, it can be deduced that the magnetic field is to the right. But the magnetic field produced by the ...
- 605
1
vote
1
answer
131
views
Emf induced by a solenoid
Could someone please clear my confusion regarding this concept and point out what is wrong with my argument:
Say we have a simple circuit as shown in the image:
Why is the potential difference ...
user343558
1
vote
0
answers
98
views
Square coil circuit and variable magnetic field problem
I am attempting to solve the following problem.
A square coil of side $l = 40.6 \ cm$ and resistor $R = 95.5 \ \Omega$ is contained within the $xy$ plane. Within the same region a magnetic field, ...
- 115