Concept explainers
(a)
The resistance of heater when it is applied
Answer to Problem 81QAP
Resistance of heater is
Explanation of Solution
Given:
Potential difference across the heater =
Mass of water =
Initial temperature of water =
Final temperature of water =
Specific heat of water =
Time up to heat is on =
Formula used:
Electrical energy consumed in heat is defined as,
Heat absorbed by water due to temperature difference is defined as,
Calculation:
It is given that
Now, substituting all these values,
Conclusion:
Thus, resistance of heater is
(b)
The difference in time interval when heater is connected with
Answer to Problem 81QAP
The difference in time interval is
Explanation of Solution
Given:
Initial voltage across the heater =
Initial time taken by heater to raise temperature of water with voltage
Potential difference across the heater when it is connected by car's battery =
Formula used:
Electrical energy consumed in heat is defined as,
Calculation:
Since, Electrical energy is defined as,
Consider the time taken by car battery is
Time difference =
Conclusion:
Thus, time difference is
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Chapter 18 Solutions
COLLEGE PHYSICS
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