All Questions
54
questions
1
vote
1
answer
49
views
Energy loss in a circuit during critical damping [closed]
I would like some intuitive explanation regarding impedance in an $RLC$ circuit.
So far, my understanding has been limited to underdamping situations where both resistance and reactance are present.
...
- 81
1
vote
1
answer
147
views
Is the closed contour integral of the Lorentz's Force equal to charge * EMF of the circuit?
I have a situation as pictured
That is, a rotating rectangular spire subject to an uniform magnetic field $\vec{B}$ (The rods to which it is attached and make the system spin is non-conductive, so it ...
0
votes
1
answer
89
views
Induced emf of a moving rod with certain velocity
I am calculating the emf of a moving rod with velocity $v$, given $v$.
My approach is to multiply
$$Blv$$
Where $l$ is the width and $v$ is the rate of change of the length.
But then I found out ...
- 103
1
vote
1
answer
351
views
Square loop above a wire with a current running through the wire [closed]
A rectangular loop is above a wire with a current running through it. If the loop is connected to an external circuit, what is the EMF generated by the loop to the circuit? There's a bit more to it ...
- 31
0
votes
1
answer
313
views
TV Channel Frequency Range Question [closed]
This is a simple texbook problem: A television channel is assigned the frequency range from 54 MHz to 60 MHz. A series RLC tuning
circuit in a TV receiver resonates in the middle of this frequency ...
- 71
0
votes
1
answer
201
views
The self inductance of the motor of an electric fan is 10 H. In order to impart maximum powr of 50 Hz, it should be connected to a capacitance of [closed]
how can i solve this
(*)The self inductance of the motor of an electric fan is 10 H. In order to impart maximum powr of 50 Hz, it should be connected to a capacitance of
what is the concept behind ...
- 15
4
votes
1
answer
184
views
Can Faraday Law be applied to a loop with some twists and turns in it?
Consider the above question. I have been able to solve the question understanding area vector of A and B are opposite in direction.
However I have some conceptual doubts.
In Faraday Law, when we say ...
- 1,568
1
vote
2
answers
3k
views
Transformers: How does current in primary coil change?
I was doing a question on transformers and found this really confusing question:
A 100% efficient transformer converts a 240V input voltage to a 12V
output voltage. The output power of the ...
- 11
0
votes
1
answer
121
views
Why the Vout vs. VR graph looks like an oval loop?
So we've performed an experiment about the resonance angular frequency and RLC circuits in the lab.
I understand that the phase of voltage on the inductor and the voltage on the capacitor are equal in ...
- 51
0
votes
1
answer
37
views
Change in ammeter's indication due to change in resistance [closed]
I stumbled on a problem in a textbook, where I was asked to describe the change in ammeter's indication due to change in resistance in circuit: rheostat's slider is moved or key is locked as indicated ...
0
votes
1
answer
59
views
Kirchhoff laws - parallel RLC
I'm having a hard time understanding why would the current flowing through the resistor in the following diagram be the sum of the currents "beside" the two AC sources.
I know the sum of ...
- 1,038
0
votes
0
answers
21
views
Relation between transformers and the resistance
I have to create a circuit where i change 240V AC into 6kV DC. The amount of Amperes that comes out of it is 30mA. Following Ohms law, would that mean I need 20,000 Ohms resistance to be able to use ...
0
votes
2
answers
101
views
Inductor in a DC circuit [closed]
I found this question,
I don't understand how could the current through 2R ,immediately after opening the circuit, be less than when the circuit is closed!
Shouldn't be an emf from the inductor that ...
- 3
4
votes
2
answers
321
views
Induced Currents in Circuits
I was given the following question:-
The plane figures shown are located in a uniform magnetic field directed away from the reader and diminishing. The direction of current induced in the loops is ...
- 220
0
votes
3
answers
2k
views
Powering an electromagnet for a long duration
Looking to power an electromagnet requiring 12 DC volts at 4 Watts, and wondering what size battery I would require to do this for 4 weeks?
My maths so far is, and I am not sure this is correct:
<...
- 1