An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater.
ScienceClass 10CBSEAnswered 27 Mar 2026
Answer
Solution:
The rate at which the heat develops in the heater can be calculated using the following formula
P = I2 R
Substituting the values in the equation, we get
P = (15A) 2 × 8 Ω = 1800 watt
The electric heater produces heat at the rate of 1800 watt
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