The Q factor of a coil is the ratio of which two parameters?

The Q factor, or quality factor, of a coil is defined as the ratio of inductive reactance to resistance. This ratio indicates how effectively the coil can store and release energy compared to the energy lost as heat due to resistance. A higher Q factor signifies that the coil has lower energy losses and better performance for applications like resonant circuits.

When the inductive reactance is high compared to the resistance, the coil is more efficient at oscillating current, which is crucial in various applications such as radio transmitters and receivers where selectivity and efficiency are key. Thus, understanding the Q factor helps technicians and engineers design better electromagnetic components.