Antennas Mock Test 10

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Question 1 of 10

1. Relation between gradient of refractive index with height and dielectric constant gradient is ____________

\(\frac{dϵ_r}{dH}=-2n \frac{dn}{dH}\)

\(\frac{dϵ_r}{dH}=n \frac{dn}{dH}\)

\(\frac{dϵ_r}{dH}=2n/\frac{dn}{dH}\)

\(\frac{dϵ_r}{dH}=2n \frac{dn}{dH}\)

Question 1 of 10

Question 2 of 10

2. Refractive index is directly proportion to ___________

1/ϵ_r

ϵ_r

\(\sqrt{ϵ_r}\)

\(1/\sqrt{ϵ_r} \)

Question 2 of 10

Question 3 of 10

3. Radio horizon is less than LOS distance.

True

False

Question 3 of 10

Question 4 of 10

4. How long the waves due to duct propagation travel following the earth curvature?

1000km

50m

5000km

15m

Question 4 of 10

Question 5 of 10

5. Find the MUF for the wave operating at a critical frequency 6MHz and having the skip distance d as 25km and virtual height of 100km in the ionosphere layer.

6.05MHz

1.025MHz

3.25MHz

1.25MHz

Question 5 of 10

Question 6 of 10

6. On which of the following factors does the LOS distance depends?

Only on height of transmitting and receiving antenna

Height of transmitting antenna alone

Height of receiving antenna alone

On height of transmitting and receiving antenna and effective earths radius factor k

Question 6 of 10

Question 7 of 10

7. The expression for refractivity in terms of the Pressure and temperature coefficient is given by ____________

\(\frac{77.6}{P}T+4810 \frac{e}{T} \)

\(\frac{77.6}{P}T+4810 \frac{T}{e} \)

\(\frac{77.6}{T}P+4810 \frac{T}{e} \)

\(\frac{77.6}{T}P+4810 \frac{e}{T} \)

Question 7 of 10

Question 8 of 10

8. Which of the following is true when a ray is incident normally in an Ionosphere region?

MUF is less than critical frequency

MUF is greater than critical frequency

MUF is equal to critical frequency

MUF is zero

Question 8 of 10

Question 9 of 10

9. Which of the following suffers the co-channel interference most?

Omni-directional

Sectored antennas

Smart antennas

Both Smart antenna and Omni-direction

Question 9 of 10

Question 10 of 10

10. Skip distance is the _____

Maximum distance at which wave returns back at the critical frequency

Minimum distance at which wave returns back at the critical angle

Minimum distance at which wave returns back at the lowest possible frequency

Maximum distance at which wave returns back at the lowest possible frequency

Question 10 of 10