Voltage Ambiguity: Alternating Currents HW

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The discussion clarifies that the "240 V a.c. supply" refers to the root mean square (r.m.s.) voltage, which is the standard convention for specifying alternating current (a.c.) voltages. The r.m.s. current of 8.0 A indicates that the heater operates under these conditions. To solve the homework question, one can calculate the resistance using Ohm's Law, mean power using the formula P = V * I, and maximum instantaneous power based on the peak voltage derived from the r.m.s. value. Understanding that 240 V is the r.m.s. voltage is crucial for accurately addressing the problem. This foundational knowledge is essential for solving related electrical engineering questions.
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A question from my HW on Alternating Currents: "When a domestic electric heater is operated from a 240 V a.c. supply, an r.m.s. current of 8.0 A flows. Assuming the heater is purely resistive, calculate its resistance, mean power and maximum instantaneous power. "

I don't know what is meant by "240 V a.c. supply". Is the question referring to the peak voltage or the r.m.s. voltage? Or is there another convention that is generally agreed to? :confused: This is all that is holding me back from answering the question. :mad:
 
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240 V is the rms voltage. It's the accepted convention for giving a.c. supply voltages.
 

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