When a constant force is applied to a body, it moves with unifrom

Options

A. Acceleration
B. Velocity
C. Speed
D. Momentum

Explanation

To solve the question, we need to analyze the relationship between force, mass, acceleration, velocity, speed, and momentum when a constant force is applied to a body. Let's break it down step by step:

### Step-by-Step Solution:

1. **Understanding the Given Information**:
- We know that a constant force is applied to a body.
- We need to determine which of the following quantities remains constant: acceleration, velocity, speed, or momentum.

2. **Using Newton's Second Law**:
- According to Newton's Second Law, the relationship between force (F), mass (m), and acceleration (a) is given by the equation:
\[ F = m \cdot a \]
- If the force (F) is constant and the mass (m) of the body is also constant, then the acceleration (a) must also be constant.

3. **Analyzing Acceleration**:
- Since the force is constant and mass is constant, we conclude that:
\[ a = \frac{F}{m} \]
- Therefore, acceleration remains constant when a constant force is applied.

4. **Analyzing Velocity**:
- Velocity is defined as the rate of change of displacement. If acceleration is constant and non-zero, the velocity of the body will change over time.
- Thus, velocity does not remain constant.

5. **Analyzing Speed**:
- Speed is the magnitude of velocity. Since velocity is changing (as established in the previous step), speed will also change.
- Therefore, speed does not remain constant.

6. **Analyzing Momentum**:
- Momentum (p) is defined as the product of mass and velocity:
\[ p = m \cdot v \]
- Since mass is constant and velocity is changing, momentum will also change.
- Hence, momentum does not remain constant.

7. **Conclusion**:
- Among the four quantities (acceleration, velocity, speed, and momentum), only acceleration remains constant when a constant force is applied to a body.

### Final Answer:
The correct option is **acceleration**.

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