Concept explainers
(a)
The magnetic field inside the solenoid.
(a)
Answer to Problem 39E
The magnetic field inside the solenoid is
Explanation of Solution
Write the expression for Ampere’s law.
Here,
Conclusion:
The magnetic field and the length of the solenoid is parallel to each other.
Rewrite equation (1).
Here,
Substitute
Here,
Thus, the magnetic field inside the solenoid is
(b)
The amount of energy stored per unit volume in the solenoid.
(b)
Answer to Problem 39E
The energy stored per unit volume of the solenoid is
Explanation of Solution
Write the expression for magnetic field inside the solenoid.
Write the expression for the magnitude of the inductance.
Here,
Substitute
Here,
Write the expression of magnetic field per unit volume of the solenoid.
Here,
Conclusion:
Substitute
Substitute
Substitute
Thus, the energy stored per unit volume of the solenoid is
(c)
The value of a constant..
(c)
Answer to Problem 39E
The value of the constant is
Explanation of Solution
Write the expression for the energy stored in a magnetic field.
Here,
Write the expression for magnetic field inside the solenoid.
Substitute
Write the expression of the energy stored in a solenoid.
Conclusion:
Compare equation (5) and (6).
Solve the above equation.
Thus, the value of the constant is
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Chapter 20 Solutions
General Physics, 2nd Edition
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