Concept explainers
A short dipole-carrying current I0 cos
(a)
A unit vector of electric field that shows the instantaneous direction of E for a short dipole.
Answer to Problem 14.1P
A unit vector of electric field that shows the instantaneous direction of E for a short dipole is
Explanation of Solution
Given:
k =1 rad/m
r = 2 m
Concept Used:
In spherical co-ordinate component of electric field is given by,
Calculation:
Plugging r =2 in above equations
Therefore,
Vector
Normalize above vector by dividing their magnitude.
Converting above equation in real instantaneous form.
Hence,
at t =0
Conclusion:
Therefore, the unit vector of electric field that shows the instantaneous direction of E for a short dipole is
(b)
The fraction of total average power is radiated in the belt
Answer to Problem 14.1P
The fraction of total average power is radiated in the given belt is 0.258.
Explanation of Solution
Given:
Concept Used:
Calculation:
Integrate above equation over the belt.
Evaluating above integral.
While total power is found by performing the same integral over
Therefore, the fraction of the total power is,
Conclusion:
Hence, the fraction of total power radiated to the given belt is 0.258.
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Chapter 14 Solutions
Engineering Electromagnetics
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