Author Question: An 800-kHz radio signal is detected at a point 2.7 km distant from a transmitter tower. The electric ... (Read 70 times)

jilianpiloj · **on:** Jul 29, 2018

An 800-kHz radio signal is detected at a point 2.7 km distant from a transmitter tower. The electric field amplitude of the signal at that point is 0.36 V/m.

Assume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed. What is the intensity of the radio signal at that point? (c = 3.00 108 m/s,
0 = 4 10-7 T m/A, 0 = 8.85 10-12 C2/N m2)
A) 170 W/m2
B) 240 W/m2
C) 340 W/m2
D) 120 W/m2
E) 86 W/m2

Question 2

An 800-kHz radio signal is detected at a point 8.5 km distant from a transmitter tower. The electric field amplitude of the signal at that point is 0.90 V/m.

Assume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed. What is the average electromagnetic energy density at that point? (c = 3.0 108 m/s, 0 = 4 10-7 T m/A, 0 = 8.85 10-12 C2/N m2)
A) 3.6 pJ/m3
B) 5.1 pJ/m3
C) 7.2 pJ/m3
D) 10 pJ/m3
E) 14 pJ/m3