When a body is in equilibrium, its acceleration is

Options

A. unity
B. positive
C. negative
D. zero

Explanation

To solve the question "When a body is in equilibrium, its acceleration is?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Equilibrium**:
- A body is said to be in equilibrium when the net force acting on it is zero. This means that all the forces acting on the body are balanced.

2. **Applying Newton's Second Law**:
- According to Newton's second law of motion, the relationship between force (F), mass (m), and acceleration (a) is given by the equation:
\[ F = m \cdot a \]

3. **Setting Up the Equation for Equilibrium**:
- Since the body is in equilibrium, we can express this condition mathematically as:
\[ F_{\text{net}} = 0 \]

4. **Substituting into Newton's Second Law**:
- If the net force is zero, we can substitute this into the equation from Newton's second law:
\[ 0 = m \cdot a \]

5. **Solving for Acceleration**:
- From the equation \(0 = m \cdot a\), we can conclude that:
\[ a = \frac{0}{m} \]
- Since mass (m) is a non-zero value (assuming the body has mass), we find that:
\[ a = 0 \]

6. **Conclusion**:
- Therefore, when a body is in equilibrium, its acceleration is **zero**.

### Final Answer:
The acceleration of a body in equilibrium is **0 m/s²**.

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