(a)
The efficiency of the battery as an energy storage device.
(a)
Answer to Problem 30P
The efficiency of the battery as an energy storage device is
Explanation of Solution
Write the expression for the energy taken by the battery.
Here,
Write the expression for the energy used.
Here,
Write the expression for power.
Here,
Use equation (III) in (II) to solve for
Use equation (III) in (I) to solve for
Write the expression for the efficiency.
Use
Conclusion:
Substitute
Substitute
Substitute
Therefore, the efficiency of the battery as an energy storage device is
(b)
The internal energy produced in the battery during one charge-discharge cycle.
(b)
Answer to Problem 30P
The internal energy produced in the battery during one charge-discharge cycle is
Explanation of Solution
Write the expression for the
Here,
Use equation (VII) to solve for
Conclusion:
Substitute
Therefore, the internal energy produced in the battery during one charge-discharge cycle is
(c)
The temperature rise during the cycle of charging and discharging.
(c)
Answer to Problem 30P
The temperature rise during the cycle of charging and discharging is
Explanation of Solution
Write the expression for the heat energy.
Here,
Use equation (IX) to solve for
The internal energy
Conclusion:
Substitute
Therefore, the temperature rise during the cycle of charging and discharging is
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Chapter 21 Solutions
Bundle: Principles of Physics: A Calculus-Based Text, 5th + WebAssign Printed Access Card for Serway/Jewett's Principles of Physics: A Calculus-Based Text, 5th Edition, Multi-Term
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