Consider the following statements (L is the length of array between centres of e

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Question
Consider the following statements (L is the length of array between centres of end antennas and A is wave-length)
1. Width of major lobe between nulls of broad side array and end fire array are different.
2. Directive gain of broadside array and end fire array are different.
3. Directive gain of broadside array is 4
Which of the above statements are correct?
Options
A. 1, 2 and 3
B. 1 and 2 only
C. 1 only
D. 1 and 3 only

Correct Answer

1 and 3 only

More questions

1. Which one of the following is true for EM wave propagation through rectangular waveguide of cross-section 2a x a
Options
A. critical wavelength for TE₁₀ mode is the same as that for TE₀₂ mode
B. critical wavelength for TE₁₀ mode is one half of that for TE₁₀ mode
C. critical wavelength for TE₁₀ mode is the same as that for TM₁₀ mode
D. critical wavelength for TE₁₀ mode is double that for TE₀₁mode

2. Minimum number of 2-input NAND gates required to implement the function F = (x + y) (Z + W) is
Options
A. 3
B. 4
C. 5
D. 6

3. The first and second subscripts in models of circular waveguides depict
Options
A. the number of full sine wave variations in circumference in direction and Bessel function variations in radial direction respectively
B. the Bessel function variations in radial direction and the number of full sine wave variations in circumference direction respectively
C. the Bessel function variations in circumference direction and number of full sine wave variations in radial direction respectively
D. none of the above

4. Which of the following is not a travelling wave?
Options
A. e = E_m sin (?x - ?t)
B. e = E_m cos (?x - ?t)
C. e = E_m sin (?t - ?x)
D. e = E_m sin (?x)

5. Consider a loss less antenna with a directive gain of + 6 dB. If 1 mW of power is fed to it the total power radiated by the antenna will be
Options
A. 4 mW
B. 1 mW
C. 7 mW
D. 1/4 mW

6. Which of these commutation methods uses an auxiliary SCR?
Options
A. Class A
B. Class B
C. Class C
D. Class D

7. In a broadcast superheterodynes receiver having no RF amplifier, the loaded Q of the antenna coupling circuit is 100. If the intermediate frequency is 455 kHz. The image frequency at 25 MHz will be
Options
A. 24.09 MHz
B. 24.54 MHz
C. 25.45 MHz
D. 25.91 MHz

8. A TR (transmitter receiver) tube has
Options
A. low loss for low power signals and high
B. high loss for low power signals and low loss for high level signal
C. low loss for both low level and high level signals
D. high loss for both low level and high level signals

10. Assertion (A): If W_F is Fermi energy, v is velocity of electron and m is mass of electron, then .
Reason (R): Conductivity of a metal depends on temperature and impurity concentration.
Options
A. Both A and R are true and R is correct explanation of A
B. Both A and R are true but R is not correct explanation of A
C. A is true but R is false
D. A is false but R is true

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