The configuration in which the Doppler radar beams are both forward and backward looking is called as?

A)
Dual
B)
Janus
C)
Redundant
D)
Wide beam

Correct Answer :   Janus

Explanation : Since the three orthogonal components of velocity are of interest, a minimum of three noncoplanar beams are required to measure the three components. Since such a beam configuration has both forward and rearward looking beams it is called Janus configuration, named after the roman god who has the ability to look backward as well as forward.

Recently Updated in Avionics Questions
Anti reflection coated optics reduce ________
A)
Refraction
B)
Reflection angle
C)
Intensity of star image
D)
Optical transmission losses

Correct Answer : Option (D) :   Optical transmission losses

Explanation : For anti-reflection coated optics, the optical transmission losses may be 1% or 2% at each air to glass or glass to air optical control surface within the telescope, including windows or sensor covers or surfaces. For uncoated optics, the loss per surface is about 4% to 5%.

The ratio of the focal length to aperture is called the ________
A)
Focal number
B)
f/ number
C)
Critical aperture
D)
Effective aperture

Correct Answer : Option (B) :   f/ number

Explanation : The ratio of focal length to aperture is called the f/ number. For example, an f/10 telescope may have a 30 in. focal length and a 3 in. aperture.

The physical size of the star depends upon _____
A)
Shape of image
B)
Colour of image
C)
Angular size of image
D)
Intensity of image

Correct Answer : Option (C) :   Angular size of image

Quick Links
Interview Questions
S/W Technology
Civil,   Mech
ECE,   EEE
More Technologies
MCQ (or) Quiz
S/W Technology
Civil,   Mech
ECE,   EEE
Aeronautical
Example Programs
C Language,   C++,   Java,   PHP,   Python
Articles
Marketing Management
Tech Updates
Tech Articles
Tools
Color Picker
Interest Calculator
EMI Calculator
Vehicle EMI Calculator
Compailers
HTML
C & CPP
PHP
Python