An electric heating coil of resistance R is immersed in 1 kg of water at 20 °C. The coil is connected in series with a resistor Y across a 240 V mains supply. The temperature of the water rises to the boiling point in 10 minutes. When Y is disconnected, the time taken for the 1 kg of water at the same temperature to boil is reduced to 6 minutes. Neglecting all heat losses, calculate the resistance R, of Y. | Specific heat capacity of water = 4200 J kg¯ K")

An electric heating coil of resistance R is immersed in 1 kg of water at 20 °C. The coil is connected in series with a resistor Y across a 240 V mains supply. The temperature of the water rises to the boiling point in 10 minutes. When Y is disconnected, the time taken for the 1 kg of water at the same temperature to boil is reduced to 6 minutes. Neglecting all heat losses, calculate the resistance R, of Y. | Specific heat capacity of water = 4200 J kg¯ K")

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 55P: A 20.00-V battery is used to supply current to a 10-k resistor. Assume the voltage drop across any...

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