Inductor help

Discussion in 'Electronics Homework Help' started by ElectStudent, Apr 8, 2014.

1. ElectStudent

13
0
Apr 8, 2014

In this circuit, the graph shows that the current rises linearly.
However, wouldn't there be a limit to how much it rises and is it actually linear because the inductor should resist current changes shouldn't it?

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2. ElectStudent

13
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Apr 8, 2014
Are these graphs correct?

In this circuit, the graph shows that the current rises linearly.
However, wouldn't there be a limit to how much it rises and is it actually linear because the inductor should resist current changes shouldn't it?

File size:
49.4 KB
Views:
77
3. BobK

7,682
1,688
Jan 5, 2010
The equation for an inductor is

dI/dt = V/L

So, with a fixed voltage across the inductor, the current will rise linearly. This is with ideal components, i.e. a voltage source that has no current limit or internal resistance, and an inductor with no series resistance. In the real world it will be limited and non-linear as you imagine.

Bob

4. ElectStudent

13
0
Apr 8, 2014
Thank you that helped a lot. I was also wondering how the current can rise so fast in an inductor? Because i was thinking inductors resist current change

5. (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,490
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Jan 21, 2010
The rising current *is* the inductor resisting a change in current.

It doesn't instantaneously rise to some figure does it?

Rather than stopping at some point, if the inductor saturates (which a theoretical inductor won't) the current will spike.