If a transformer rating 240vac 50hz being supplied by a source 240vac 60hz,will it get hotter than by 240vac 50hz source?
Hard to say. higher frequency lower magnetization current lower copper losses but higher magnetic losses. It depends on specific construction of the transformer. Roughly I'd say no significant change in heat dissipation.
Yes. higher frequency higher energy. To Might i: that video is awesome!
Keep in mind that every hertz reverses the flow of the electrons. The more hertz, the more reverses. Each reverse involves friction, which generates heat.
Inductive Reactance increases proportionally with frequency. Therefore, if the supply voltage remains the same but the frequency increases, the impedance increases. This will lead to an increase in heat. If the supply voltage remains the same but the frequency decreases, the impedance decreases, which means that less heat is produced. The answer to your question is NO.
