Is stress a vector quantity ?

Explanation

To determine whether stress is a vector quantity, we can analyze the definition and properties of stress step by step.

### Step 1: Definition of Stress
Stress is defined as the internal reaction force per unit area within materials when they are subjected to external forces. Mathematically, it can be expressed as:
\[ \text{Stress} = \frac{\text{Internal Reaction Force}}{\text{Area}} \]

**Hint:** Consider how stress is calculated and what quantities are involved in this calculation.

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