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What is the approximate velocity of a radio wave as it travels through free space?

  1. 150,000,000 meters per second

  2. 300,000,000 meters per second

  3. 450,000,000 meters per second

  4. 600,000,000 meters per second

The correct answer is: 300,000,000 meters per second

The approximate velocity of a radio wave as it travels through free space is about 300,000,000 meters per second, which is indeed the speed of light in a vacuum. This speed is a fundamental constant of nature and applies not just to radio waves but to all forms of electromagnetic radiation. In free space, radio waves propagate at this speed due to the absence of obstacles or materials that could slow them down. Factors like the medium through which the waves travel (such as air, water, or glass) can affect the speed, but in free space, they travel at this maximum speed. Understanding this principle is essential in fields like telecommunications and radio broadcasting, where the transmission of signals relies heavily on the speed of electromagnetic waves. This knowledge helps in the calculation of distances and timing involved in various applications, such as GPS technology and radio communication systems.