Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

Looking for something else?

Not the answer you are looking for? Search for more explanations.

- anonymous

Doubt about inductance
Suppose I have an ideal circuit with zero resistance and some inductance L = 1H say and hooked up to an ideal battery of say 5V. And I thrown in the switch.
I know that the moment I throw in the switch, a huge di/dt causes a back emf, which is exactly equal to the source voltage, -5V.
And yet the current keeps growing in the circuit.?
How is that possible? I fully understand that the emf exists BECAUSE THERE IS A di/dt, if there was no di/dt, there wouldn't be the back emf. so clearly the current must 'accelerate', but I fail to convince myself 'what'

At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga.
Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus.
Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.

Get our expert's

answer on brainly

SEE EXPERT ANSWER

Get your **free** account and access **expert** answers to this

and **thousands** of other questions.

Get your **free** account and access **expert** answers to this and **thousands** of other questions

- anonymous

- katieb

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

Get this expert

answer on brainly

SEE EXPERT ANSWER

Get your **free** account and access **expert** answers to this

and **thousands** of other questions

- anonymous

What is accelerating my current?
Because the field due to the battery, is cancelled by the induced field due to the back emf. So what is 'causing' the current to grow?

- anonymous

- Vincent-Lyon.Fr

It is a continuous process.
If the increase in i becomes less (because of you counter voltage), then E will be once again greater than the (reduced) counter-voltage. SO an increase in i would follow, etc.
Of course the sytem does not work in such a steps-like way, because all these changes happen with the speed of light across the circuit. So the evolution is continuous.

Looking for something else?

Not the answer you are looking for? Search for more explanations.

- Michele_Laino

substatially an inductor is a metal wire whose resistance is negligible, so in order to draw a circuit with an inductor only, and a generator of energy, we have to use only a generator of alternating voltage, otherwise we can damage our inductor, namely:
|dw:1441364706797:dw|
now an emf exists, only because our \(\Large E(t)=E_0 \cos(\omega t)\) is a sinusoidal function, so we can write the subsequend differential equation:
\[\Large L\frac{{di}}{{dt}} = {E_0}\cos \left( {\omega t} \right)\]
whose solution is:
\[\Large i\left( t \right) = \frac{{{E_0}}}{{\omega L}}\sin \left( {\omega t} \right)\]
which is an oscillating function, being \( \Large E_0 \) a real constant

- Michele_Laino

subsequent*

- anonymous

@Vincent-Lyon.Fr
I like to think of
E = - L di/dt
as F = m dv/dt
just as you push the rock with some force, the rock pushes you back with the force m dv/dt
But the big difference is, when I push the rock, the counter force is on ME, and so the rock keeps accelerating.
So that is what is bugging me, cause here, the -Ldi/dt and the potential difference V are acting on the same 'thing' right?
@michele_laino
I was not talking about the math :D.. Just a conceptual doubt!

- anonymous

@Vincent-Lyon.Fr
But I perfectly understood what you meant, by a continuous process..

Looking for something else?

Not the answer you are looking for? Search for more explanations.