State the essential condition for the addition of vectors.

Explanation

To state the essential condition for the addition of vectors, we need to consider the following steps:

### Step-by-Step Solution:

1. **Identify the Physical Quantity**: The first step is to recognize that vectors represent physical quantities. Examples of vectors include force, velocity, displacement, and acceleration.

2. **Same Physical Quantity**: The essential condition for the addition of vectors is that the vectors must represent the same physical quantity. For instance, you can add two forces together, but you cannot add a force vector to a displacement vector.

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