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Why are television broadcasts on Earth generally not receivable beyond about 100 km from the transmitting station?

1. Because the receiving antenna cannot pick up the signal after that distance
2. Because a TV broadcast contains both sound and picture components
3. Because television signals are weaker than radio signals
4. Because the Earth's surface is curved like a sphere

Correct answer: Because the Earth's surface is curved like a sphere

Solution

The curvature of the Earth limits the line of sight between the transmitting station and the receiver, causing signals to become obstructed beyond a certain distance, typically around 100 km.

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