Concept explainers
(a)
The magnitude of the force, which is exerted on an electron in time varying magnetic field.
(a)
Answer to Problem 39P
The magnitude of the force which is exerted on an electron in time varying magnetic field is
Explanation of Solution
Follow the right-handed cylindrical coordinate system.
Write the expression for Faraday’s law.
Here,
Write the expression for area.
Here,
Write the expression for length element.
Here,
Write the expression for magnitude of force on electron.
Here,
Let the electric field be in clockwise
Substitute
Substitute
Conclusion:
Substitute
Therefore, the magnitude of the force on electron is
(b)
The direction of the force, which is exerted on an electron in time varying magnetic field.
(b)
Answer to Problem 39P
The direction of force exerted on an electron is clockwise if seen from above.
Explanation of Solution
The direction of the electric field has to be in the clockwise direction. It is clear from equation (I) that the direction of
Therefore, direction of force exerted on the electron is clockwise if seen from above.
(c)
The time when force on the electron is equal to zero.
(c)
Answer to Problem 39P
The force on the electron is equal to zero at
Explanation of Solution
In the time varying magnetic field, force on the electron must be zero for particular instant of time.
Conclusion:
Substitute
Further solve the equation.
Therefore, force on electron is equal to zero at
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Chapter 31 Solutions
Bundle: Physics for Scientists and Engineers with Modern Physics, Loose-leaf Version, 9th + WebAssign Printed Access Card, Multi-Term
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