You are very welcome. I assume your question related to the calculation of area of hysteresis loop. Using oscilloscope, we need to perform same calculation and integration to identify the area of the hysteresis loop. The scope just plot the cycle for us. Therefore, we need to ensure the proper scale of the BH curve and perform the integration. The advantage of the empirical formula is that we can calculate the area of the hysteresis loop during the design stage. That means, we can calculate the area of the loop even before the implementation of the magnetic circuit. Hope, this answer your question. Thanks
Thank you for your question. There is no friction between the magnets. Basically, the hysteresis effect is the cause of the heat loss inside the magnetic core. Due to hysteresis effect the input source energy flowing in is greater than the returned energy. Therefore, during one cycle (or hysteresis cycle) there is a net energy (flowing in energy - returned energy = non-zero energy value). This net energy always flow from the source to the core and does not return. This net energy dissipated inside the core as a heat. I know it easy for us to understand the heat loss that cause because of the friction. So now we need to also that the hysteresis is also another phenomena that cause heat loss.
The current "i" in the power formula is instantaneous current. You can also review the sinusoidal excitation lecture to get more idea about the hysteresis loss.
