All Questions
Tagged with electricity electric-current
791
questions
1
vote
2
answers
682
views
Calculate power $P=V \times I$
I have an adapter which mentions like this...
Input: 100-240V~1.8A
50-60hZ
So how much power does it really consume?
I just knew ...
- 111
2
votes
1
answer
4k
views
Residual Resistivity in alloys and metals
Residual Resistivity
I saw that the graph of resistivity to temperature of alloys like nichrome is like so
Meaning that even at 0 K it has some resistivity just like copper :
I read some where "...
- 950
2
votes
2
answers
422
views
Fundamentality of voltage to current
From Ohm's Law :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points.
I would like to know if ...
- 950
22
votes
6
answers
92k
views
In an alternating current, do electrons flow from the source to the device?
If electrons in an alternating current periodically reverse their direction, do they really flow? Won't they always come back to the same position?
- 221
3
votes
1
answer
2k
views
How does a voltage independent current source work?
I'm having some trouble understanding what a voltage-independent current source is. How can you have a current without a voltage? As I understand it, voltage or EMF is the force that drives the ...
- 153
1
vote
1
answer
11k
views
Current against the inverse of resistance graph, $I = V/R +c$
If I have a plot of current ($y$ axis) against 1/Resistance ($x$ axis).
The circuit it is measured from is a simply 2 resistors connected in parallel to battery, where the potential across the ...
- 6,927
78
votes
11
answers
56k
views
Why is the charge naming convention wrong?
I recently came to know about the Conventional Current vs. Electron Flow issue.
Doing some search I found that the reason for this is that Benjamin Franklin made a mistake when naming positive and ...
- 1,291
1
vote
4
answers
1k
views
Do Alkaline batteries, $\mathrm{NiMH}$, rechargeable alkaline, Lithium $\mathrm{AA}$, all have similar MAX POWER?
So in physics, one smart teacher told me,
$$
V = IR
$$
or
$$
I = \frac{V}{R}
$$
but it is not always true, because $P = VI$ and each power supplying device (such as battery) has a "maximum power" it ...
- 332
11
votes
7
answers
21k
views
Difference between current and voltage sources
I am confused about the current and voltage. My intuitive example would be that of a pipe of say water. The diameter of the pipe determines the amount of water flowing per second but the pressure is ...
- 211
2
votes
0
answers
817
views
Skin effect and currents
Here in this picture
you can see $I_W$ which is induced by H.
But why $I_W$ is not vice versa?
Because of
$$rot \, \vec B = \mu_0 \, \left( \varepsilon_0 \frac{\partial \vec{E}}{\partial t} + \vec j \...
- 919
-4
votes
1
answer
196
views
Amount of 2 amperage [closed]
I have 2 equation describing the alternating amperage $I_1$ and $I_2$. I need to get amount of these amperages.
My equations:
$$I_1=10\sin(\omega t+30)$$
$$I_2=20\sin(\omega t-50)$$
How can i make ...
- 109