Concept explainers
The resistance of a heating coil which is used to raise the temperature of
Answer to Problem 30SP
Solution:
The resistance of the heat coil is
Explanation of Solution
Given data:
Mass of water is
Initial temperature of water is
Final temperature of water, that is boiling point of water, is
Time required to change the temperature is
The line is of
Formula used:
The expression of heat is written as,
Here,
The expression of energy is written as,
Here,
Explanation:
The expression to convert initial temperature from degree Celsius to Kelvin is
Here,
Substitute
The expression to convert final temperature from degree Celsius to Kelvin is
Here,
Substitute
Recall the expression of heat.
Substitute
Understand that the
Here,
Substitute
Understand that the total heat is equal to the energy dissipated by the heater coil.
Recall the expression of dissipated energy.
Substitute
Conclusion:
Therefore, the resistance of the required heat coil is
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Chapter 27 Solutions
Schaum's Outline of College Physics, Twelfth Edition (Schaum's Outlines)
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