When a wave coming from a medium where its velocity is………………meets a medium where its velocity is………………, it is reflected back with a reversal of phase.

Explanation

To solve the question, we need to understand the relationship between the velocity of a wave in different media and the conditions for reflection with a reversal of phase.

### Step-by-Step Solution:

1. **Understanding Wave Reflection**: When a wave travels from one medium to another, it can either be transmitted into the second medium or reflected back into the first medium. The behavior of the wave at the boundary between the two media depends on the properties of those media.

2. **Identifying the Media**: Let's denote the first medium (where the wave is coming from) as Medium 1 and the second medium (where the wave is going) as Medium 2. We will denote the velocity of the wave in Medium 1 as \( v_1 \) and in Medium 2 as \( v_2 \).

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