SI units of stress is

Options

A. `Nm^(2)`
B. Nm
C. `Nm^(-2)`
D. `Nm^(-1)`

Answer

To find the SI unit of stress, we can follow these steps:

### Step 1: Understand the definition of stress
Stress is defined as the force applied per unit area. Mathematically, it can be expressed as:
\[ \text{Stress} = \frac{\text{Force}}{\text{Area}} \]

### Step 2: Identify the SI unit of force
The SI unit of force is the Newton (N). Therefore, we have:
\[ \text{Force} = 1 \, \text{N} \]

### Step 3: Identify the SI unit of area
The SI unit of area is square meters (m²). Thus, we have:
\[ \text{Area} = 1 \, \text{m}^2 \]

### Step 4: Substitute the units into the stress formula
Now, substituting the units of force and area into the stress formula, we get:
\[ \text{Stress} = \frac{\text{N}}{\text{m}^2} \]

### Step 5: Express the unit in standard form
This can be rewritten as:
\[ \text{Stress} = \text{N} \cdot \text{m}^{-2} \]

### Step 6: Conclusion
Thus, the SI unit of stress is:
\[ \text{N/m}^2 \text{ or } \text{Newton meter}^{-2} \]

### Final Answer
The SI unit of stress is Newton per square meter (N/m²) or Newton meter to the power of minus two (N·m⁻²).

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