The acceleration of a particle is found to be non zero while no force acts on the particle. This is possible if the measurement is made from

Options

A. inertial frame
B. non inertial frame
C. both
D. some times inertial (or) some times non inertial

Answer

To solve the problem, we need to analyze the situation where a particle has a non-zero acceleration while no external force is acting on it. This scenario can occur when the measurements are made from a specific type of reference frame.

### Step-by-Step Solution:

1. **Understanding the Problem**:
- We are given that a particle has a non-zero acceleration while no force acts on it. This situation is contradictory according to Newton's first law, which states that an object at rest will remain at rest, and an object in motion will remain in motion unless acted upon by a net external force.

2. **Identifying the Reference Frame**:
- The key to resolving this contradiction lies in the choice of the reference frame from which the acceleration is measured. If the observer is in an inertial frame (a non-accelerating frame), then the particle should not have any acceleration if no net external force is acting on it.

3. **Considering Non-Inertial Frames**:
- If the observer is in a non-inertial frame (an accelerating frame), the observer may perceive the particle to have an acceleration even in the absence of a net external force. This is because in a non-inertial frame, fictitious or pseudo forces come into play.

4. **Applying Pseudo Force**:
- In a non-inertial frame, an observer will apply a pseudo force to account for the acceleration of the frame itself. This pseudo force is not a real force acting on the particle but is used to explain the observed acceleration from the perspective of the accelerating observer.

5. **Conclusion**:
- Therefore, the acceleration of the particle being non-zero while no force acts on it is possible if the measurement is made from a non-inertial frame of reference.

### Final Answer:
The acceleration of a particle can be non-zero while no force acts on it if the measurement is made from a non-inertial frame of reference.

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