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## #1 Re: Help Me ! » I'm in trouble of 10 and exponent math. » 2021-01-03 05:36:48

Got it.  I was using the wrong button on the calculator.  I was using the exponent button instead of power button.  Thanks!!!!!

## #2 Re: Help Me ! » I'm in trouble of 10 and exponent math. » 2021-01-03 03:39:52

Good morning Bob and thanks for your help.  Yes I am using the exponent key on a calculator.
No matter how I do this, problem (A) is supposed to resolve to 20A.  I get 200A using the equation given in (A)

The textbook equation is give in (A) without any changes.  So I ask, what am I doing wrong in my evaluation of the formula?   Is it possible that the formula is incorrect or the answer given is incorrect?

## #3 Help Me ! » I'm in trouble of 10 and exponent math. » 2021-01-02 07:33:06

don.farr
Replies: 4

A)    VL =    Δi /Δt
(200*10-6) ((200*10-3)/2*10-6)
0.002       ((   2        ) / 0.00002)
0.002 * 1OOOOO
200V

B)    VL =    Δi /Δt
(200*1.0e-6) ((200*10-3)/2*10-6)
0.02       ((   2        ) / 0.00002)
0.0002 * 1OOOOO
20V

Where VL = Instant voltage on an inductor
Δi = Change in amperage
Δt – Change in time

The answer given in the textbook is “20 volts” However, using the book’s formula (A) I come up with 200V instead of the answer of 20V
So I created process “B” and I get the correct answer, but I cannot not explain why there is a difference between using the “Micro value (10-6) and using the exponent value 1.0e-6”