Question

A certain radar installation tracks airplanes by transmitting electromagnetic radiation of wavelength 4.0 cm.

Answer 1

Answer:

a) frequency = $7.5 \times 10^9 hz$

b) times = $3.2 \times 10^{-5} s$

Explanation:

Part a)

As we know that frequency of radiation is given as

$frequency = \frac{speed}{wavelength}$

now we know that

$speed = 3 \times 10^8 m/s$

$wavelength = 4 cm$

now frequency is given as

$f = \frac{3 \times 10^8}{4 \times 10^{-2}}$

$f = 7.5 \times 10^9 Hz$

Part b)

Time required for the pulse to reach the airplane and return is given by formula

$t = \frac{distance}{speed}$

total distance for moving to and fro = 4.8 km + 4.8 km = 9.6 km

speed of the wave = $3 \times 10^8 m/s$

now times is given as

$t = \frac{9.6 \times 10^3}{3 \times 10^8}$

$t = 3.2 \times 10^{-5} s$

Answer 2

the wavelength equation is

speed (of light in this case)= wavelength (m) x frequency

3x10^8m/s / .07m = f

frequency= 4 285 714 286 hertz

 

 

 

b) Total distance= 4.8 km (4,800 m)

Speed = 3x10^8 m/s

d=st

t= d/s

t= 4,800 m/3x10^8m/s

t= 1x10^-5 seconds