# Friis Transmission Equation Online Exam Quiz

Friis Transmission Equation GK Quiz. Question and Answers related to Friis Transmission Equation. MCQ (Multiple Choice Questions with answers about Friis Transmission Equation

### An ideal source in which the power is radiated equally in all directions is called as __ radiator.

**Options**

A : Isotropic

B : Omni-directional

C : Directional

D : Transducer

### Assume two similar antennas for transmitting and receiving. If the operating frequency gets reduced by 3 times then the received power gets ___

**Options**

A : increases by factor 3

B : decreases by factor 3

C : increases by factor 9

D : decreases by factor 9

### Find the effective length of a receiving antenna with open circuit voltage 1V and incident electric field 200mV/m?

**Options**

A : 0.2m

B : 50m

C : 5m

D : 5cm

### Find the power received by the receiving antenna if it is placed at a distance of 20m from the transmitting antenna which is radiating 50W power at a frequency 900MHz and are made-up of half-wave dipoles.

**Options**

A : 23.65?W

B : 2.365?W

C : 236.5?W

D : 4.73?W

### For an isotropic source, Radiation intensity will be ___ on ? and __ on ?.

**Options**

A : Dependent, independent

B : Independent, independent

C : Independent, dependent

D : Dependent, dependent

### If the distance between the transmitting and receiving antenna is decreased by a factor 2 while other factors remain same, then the new power received by the antenna ___

**Options**

A : increases by factor 2

B : decreases by factor 2

C : increases by factor 4

D : decreases by factor 4

### In Isotropic radiation, which of the following vector component is absent in pointing vector?

**Options**

A : \widehat{a_r}

B : \widehat{a_\theta}

C : \widehat{a_\emptyset}

D : Both \widehat{a_\theta} and \widehat{a_\emptyset}

### Let's assume a transmitting antenna having gain 10dB is placed at a distance of 100m from the receiving antenna and radiates a power of 5W. Find the gain of the receiving antenna in dB when the received power is 150?W and transmitter frequency 500MHz?

**Options**

A : 1.31dB

B : 1.19dB

C : 11.19dB

D : 13.16dB

### Power received by the antenna when one antenna is horizontally polarized and the other is vertically polarized is ___

**Options**

A : 1

B : 0

C : \frac{P_r}{P_t} = \frac{G_t G_r ?^2}{(4?R)^2}

D : \frac{P_r}{P_t} = \frac{G_t G_r ?^2}{2(4?R)^2}

### What is the amount of Electric field present at a distance of 10km for an isotropic radiator with radiating power 3kW?

**Options**

A : 30mV/m

B : 60mV/m

C : 15mV/m

D : 10mV/m