Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Communication

Question:

A 1 KW signal is transmitted using a communication channel which provides attenuation at the rate of 2 dB per km. If the communication channel has a total length of 5 km, what is the power of the signal received ?

(gain in dB = 10 log \(\frac{P_{o}}{P_{i}}\)

Options:

900 W

100 W

990 W

1010 W

Correct Answer:

100 W

Explanation:

Pi = 1 kW = 1000 W

length of path = 5 Km

Loss of power at a distance of 5 km = 2 x 5 = 10 dB

gain in dB = -10 log \(\frac{P_{i}}{P_{o}}\)

Po = 100 W