Complete the following statement: An inertial reference frame is one in which

Options

A. Newton's first law of motion is valid.
B. the inertias of objects within the frame are zero.
C. the frame is accelerating.
D. the acceleration due to gravity is greater than zero `"m"//"s"^(2)`.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Inertial Reference Frame:**
An inertial reference frame is defined as a frame of reference in which an object either remains at rest or moves at a constant velocity unless acted upon by a net external force. This means that there is no acceleration in this frame.

2. **Characteristics of Inertial Reference Frame:**
- In an inertial frame, the laws of motion, particularly Newton's first law, hold true. This law states that an object will maintain its state of rest or uniform motion unless acted upon by an external force.
- The acceleration in an inertial frame is zero, which implies that there are no unbalanced forces acting on the objects within that frame.

3. **Examples of Inertial Reference Frames:**
- A bus moving at a constant speed on a straight road can be considered an inertial frame. Inside this bus, passengers experience no net force acting on them, and they do not feel any push or pull unless the bus accelerates or decelerates.
- Similarly, a spaceship traveling in deep space far from gravitational influences and moving at a constant velocity is also an inertial frame.

4. **Conclusion:**
Therefore, the complete statement is: "An inertial reference frame is one in which there is no acceleration (the acceleration is zero)."

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