TailieuVNU.com Electromagnetic Engineering ELT2036.[r]
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li Electromagnetic Engineering (ELT2036) [Ve
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Question 1: (3 points)
A 5cmx 5 cm flat plate is located 10 cm from a point charge of q=3x10-8C as in
figure below What is the electric flux through the plate due to the point charge?
10 cm 5cm
5cm
Question 2: (3 points)
A 150-turn rectangular coil of wire with sides of 25 and 40 cm rotates about a
horizontal axis in a vertical magnetic field of 3.5 mT How fast this coil rotate for
the induced emf to reach 7 V?
Hint: The angle of rotation @=atwhere wis angular frequency of the coil
Question 3: (2 points)
The electric vector of a uniform plan wave in free space is given by
E =5exp{—j27(0.6x+ 0.82) + jor}
Show that the given electric field is satisfied the wave equation provided that @ has
a certain value Evaluate the propagation constant k, the wave length 2, and the
angular frequency @ of the given electric field Also, find the direction of
propagation of the plane wave
Question 4: (2 points)
From the equations: VxH =J+ = VxE= Bo VJ=- = prove that for time-
f Ct t
varying fields, we have VB=0 and V.D=p
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