Through which mode of propagation, the radio waves can be sent from one place to another ? (A) ground wave propagation (B) sky wave propagation (C) space wave propagation (D) all of them

Ground wave propagation: This mode of propagation involves radio waves traveling along the surface of the Earth. Ground waves can follow the curvature of the Earth, making it suitable for short to medium distances. Sky wave propagation: This mode relies on radio waves bouncing off the ionosphere, a layer of charged particles in the Earth's upper atmosphere. This mode is effective for medium to long-range communication, as the waves can bounce back to the Earth's surface at great distances. Space wave propagation: This mode involves radio waves traveling through the Earth's atmosphere and space. It is commonly used for satellite communication and has a direct line of sight between the transmitter and receiver.

Now that we have examined each mode of propagation, we can determine the correct answer. (A) ground wave propagation is suitable for short to medium distances (B) sky wave propagation is effective for medium to long-range communication (C) space wave propagation is used for satellite communication Through these modes of propagation, radio waves can be sent from one place to another. Therefore, the correct answer is: (D) all of them.