State the essential condition for the addition of vectors.

Explanation

To answer the question regarding the essential condition for the addition of vectors, we can break it down into clear steps:

### Step-by-Step Solution:

1. **Understanding Vectors**: Begin by recognizing that vectors are quantities that have both magnitude and direction. Examples include displacement, velocity, force, etc.

2. **Identifying the Condition**: The essential condition for the addition of vectors is that they must represent the same physical quantity. This means that if one vector represents a certain type of physical quantity, the other vector must represent the same type.

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