In an iron-cored choking coil (also known as an inductor), the power dissipation primarily occurs due to the resistance of the wire used in the coil. The power dissipation is given by the formula:
P = IĀ²R
Where:
P is the power dissipation (in watts)
I is the current flowing through the coil (in amperes)
R is the resistance of the wire in the coil (in ohms)
Since the iron core of the choking coil is primarily used to increase the inductance (the ability to store energy in a magnetic field) of the coil, it usually doesn't significantly contribute to power dissipation, assuming the core is not operating in its magnetic saturation region.
For an ideal inductor, where there is no resistance in the coil itself (R = 0), the power dissipation would be zero, regardless of the current flowing through it. However, in real-world scenarios, there is always some resistance in the wire, so power will be dissipated in the form of heat due to the current passing through the resistance.
If you have more specific details about the choking coil, such as the resistance of the wire and the current flowing through it, I can help you calculate the power dissipation more accurately.