How can one create plane waves and slpherical waves?

Explanation

To create plane waves and spherical waves, we can follow these steps:

### Step-by-Step Solution:

1. **Creating Spherical Waves:**
- **Use a Point Source:** Spherical waves can be generated using a point source. A point source is an idealized source of waves that emits energy uniformly in all directions.
- **Wave Emission:** When the point source emits waves, they propagate outward in spherical shapes. The wavefronts are concentric spheres centered around the point source.

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