Briefly explain the two ways by which radio waves are propagated in atmosphere.

Explanation

### Step-by-Step Solution:

1. **Understanding Radio Wave Propagation**:
Radio waves can travel through the atmosphere in different ways. The two primary methods of propagation are ground wave propagation and sky wave propagation.

2. **Ground Wave Propagation**:
- **Definition**: Ground wave propagation occurs when radio waves travel along the surface of the Earth.
- **Mechanism**: In this method, the waves are transmitted from a transmitting antenna to a receiving antenna that is located near the Earth's surface. The radio waves follow the curvature of the Earth and can bend slightly due to the Earth's surface.
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