What EMF is produced if a waffle iron that draws 2.5 amperes and has an inductance of 560 millihenries is suddenly unplugged, so the current drops to essentially zero in 0.015 seconds

93 V

Explanation:

use the expression for induced emf as

EMF = L dI/dt

L = 560 x 10⁻³

dI = 2.5 A  

dt = 0.015 s = 15 x 10⁻³ s

EMF = L dI/dt

= 0.560 * 2.5/0.015

= 93.33 V

≅ 93 V

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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