An LC circuit has an inductance of 20 mH and a capacitance of 5.0 $\mu$F.If the charge amplitude is 40 $\mu$C, what is the current amplitude?
A)0.025 A
B)0.13 A
C)1.0 A
D)7.9 A
E)400 A

Question

Quizplus · Accepted Answer

We can use the formula for the angular frequency of an LC circuit:

ω = 1/sqrt(LC)

Plugging in the given values, we get:

ω = 1/sqrt(20 mH × 5.0 μF) = 1000 rad/s

We can also use the formula for the current amplitude in an LC circuit:

I = QωL

Plugging in the given values, we get:

I = (40 μC) × (1000 rad/s) × (20 mH) = 0.08 A

Therefore, the current amplitude is 0.08 A or 80 mA, which is closest to answer choice B, 0.13 A.

An LC Circuit Has an Inductance of 20 MH and a Capacitance