The Q of an LC circuit is given by ___________

The correct answer is: C. 2pfrL / R

The Q factor of an LC circuit is a measure of its quality. It is defined as the ratio of the energy stored in the inductor to the energy dissipated in the resistor per cycle. The higher the Q factor, the more efficient the circuit is at storing and releasing energy.

The Q factor can be calculated using the following formula:

Q = 2πfL / R

where:

• f is the frequency of the oscillation
• L is the inductance of the inductor
• R is the resistance of the resistor

Option A is incorrect because it does not include the inductance of the inductor. Option B is incorrect because it does not include the resistance of the resistor. Option D is incorrect because it does not include the frequency of the oscillation.