At a given instant the current and self induced emf is an inductor are directed from the left to right, with negative (-) on the left, and positive (+)on the right.
Is the current increasing, or decreasing?
The induced emf is 17 V and the rate of change of the current is 25 kA/s; find the inductance.
Explain your work, and good luck! :)
2007-04-11 08:52:35 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
-vs+vs-=pi to the ratio on any given state.
2007-04-11 09:00:04 · answer #1 · answered by colodge_25 3 · 0⤊ 0⤋
V(t) = L * d i(t) / dt
d i(t) / dt is given as 25 kA/s
V(t) is given as 17 V
So L is 680 microHenries
The direction of the voltage is positive with respect to an external current entering the inductor at the positive end of the voltage across the inductor.
Since the current is reversed from the definition (above), it must be "internal" from the "discharge" of magnetic energy, therefore the current is decreasing.
.
2007-04-11 09:02:46 · answer #2 · answered by tlbs101 7 · 0⤊ 0⤋
since V=L*di/dt, V=17 and di/dt=25K
solving for L leave .00068
2007-04-11 09:00:52 · answer #3 · answered by PCB Designer 2 · 0⤊ 0⤋