Physics
Physics
Problem
An immersion heater marked “, ” is used for every day throughout the month of June. (a) Calculate the total electrical energy consumed by the heater during the month, expressing your answer in kilowatt–hour. (b) If the electricity tariff is Rs per kilowatt–hour, determine the amount to be paid for operating the heater in June.Intuitive explanation
This problem is about converting the power rating and operating time into total energy consumption, then using that to find cost. The key insight is that energy equals power multiplied by time—so once you know how many hours the heater runs over the entire month, multiplying by its power rating gives you the total kilowatt-hours used. Then cost is just a straightforward multiplication by the tariff rate.
Intuitive explanation
This problem is about converting the power rating and operating time into total energy consumption, then using that to find cost. The key insight is that energy equals power multiplied by time—so once you know how many hours the heater runs over the entire month, multiplying by its power rating gives you the total kilowatt-hours used. Then cost is just a straightforward multiplication by the tariff rate.