Answer:
120 m
Explanation:
Given:
wavelength 'λ' = 2.4m
pulse width 'τ'= 100T ('T' is the time of one oscillation)
The below inequality express the range of distances to an object that radar can detect
τc/2 < x < Tc/2 ---->eq(1)
Where, τc/2 is the shortest distance
First we'll calculate Frequency 'f' in order to determine time of one oscillation 'T'
f = c/λ (c= speed of light i.e 3 x
m/s)
f= 3 x
/ 2.4
f=1.25 x
hz.
As, T= 1/f
time of one oscillation T= 1/1.25 x
T= 8 x
s
It was given that pulse width 'τ'= 100T
τ= 100 x 8 x
=> 800 x
s
From eq(1), we can conclude that the shortest distance to an object that this radar can detect:
= τc/2 => (800 x
x 3 x
)/2
=120m
Answer:
3.82 Hertz
Explanation:

This is the equation of a wave which varies sinusoidally.
The standard equation of a wave is given by

where, A be the amplitude of the wave, k be the wave number, x be the displacement of wave, ω be the angular frequency and t be the time taken, and Ф be the phase angle.
now compare the given equation by the standard equation, we get
k = 3
ω = 24
Ф = π / 2
So, the angular frequency = 24
The relation between the angular frequency and the frequency is given by
ω = 2 x π x f
24 = 2 x 3.14 x f
f = 3.82 Hertz
Answer:
Explanation:
For Doppler effect in radar the formula is as follows
Δf = f₀ x 2v /c
Δf is change in frequency in reflected wave , f₀ is original frequency , v is velocity of source and c is velocity of right .
Δf = 2460 Hz , f₀ = 1.0525 x 10¹⁰ Hz , v = ? c is velocity of light .
2460 = 1.0525 x 10¹⁰ x 2 v / 3 x 10⁸
2460 = 105.25 x 2 v / 3
v = 2460 x 3 / (105.25 x 2 )
v = 35 .06 m /s .
(b)
Since the observed frequency is less , the source is moving away from the observer .
option (2) is correct .
Answer:
Diurnal motion, apparent daily motion of the heavens from east to west in which celestial objects seem to rise and set, a phenomenon that results from the Earth's rotation from west to east. The axis of this apparent motion coincides with the Earth's axis of rotation. Retrograde motion is an APPARENT change in the movement of the planet through the sky. It is not REAL in that the planet does not physically start moving backwards in its orbit. It just appears to do so because of the relative positions of the planet and Earth and how they are moving around the Sun.