Why are the ceilings of concert halls curved ?

Explanation

### Step-by-Step Solution:

1. **Understanding Sound Propagation**: Sound travels in waves and can reflect off surfaces. The way sound reflects off a surface can affect how well it is heard in a space.

2. **Types of Ceilings**: There are two main types of ceilings to consider: plain (flat) ceilings and curved ceilings.

3. **Reflection from a Plain Ceiling**: When sound waves hit a flat ceiling, they reflect at a small angle. This means that the sound is directed in a narrow path, which may not reach all areas of the concert hall effectively. As a result, some audience members may not hear the performance clearly.

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