Electronics and Communication Engineering - Electromagnetic Field Theory

26.
The critical frequency of 'F' layer is greater than 30 MHz.
True
False
Answer: Option
Explanation:
No answer description is available. Let's discuss.

27.
Which of the following statement is incorrect?
Z0 is an ac characteristic that is the same for any length of time
The characteristic impedance can be measured approximately with a sensitive ohm meter
A line terminated in its Z0 is a flat or non-resonant line
A twin lead has higher Z0 but lower losses than coaxial cable
Answer: Option
Explanation:
No answer description is available. Let's discuss.

28.
Which of the following will increase the antenna radiation efficiency?
Use of larger section of conductor
Providing insulation on conductor
Top loading of antenna
Any of the above
Answer: Option
Explanation:
No answer description is available. Let's discuss.

29.
A waveguide operated below cut off frequency can be used as
phase shifter
an attenuator
an isolator
none
Answer: Option
Explanation:
No answer description is available. Let's discuss.

30.
A time varying field is applied to a circuit with a capacitor- which of the following statements is correct?
The conduction current is equal to the displacement current
The conduction current density is J and displacement current density
The current in the circuit consists of conduction current and displacement current
The displacement current passes through the capacitor
Answer: Option
Explanation:
No answer description is available. Let's discuss.