There are some steel balls in an iron box. They will behave

Options

A. like a non-rigid body, because the material of box and balls is different.
B. like a non-rigid body, because the balls in the box are not stuck at a point.
C. like a rigid body, because the box and the balls are rigid bodies.
D. like a rigid body, as the box and the balls are solids.

Answer

To solve the question regarding the behavior of steel balls in an iron box, we need to analyze the definitions and characteristics of rigid and non-rigid bodies.

### Step-by-Step Solution:

1. **Understanding Rigid Bodies**:
- A rigid body is defined as a solid object in which the distance between any two points remains constant, regardless of the forces applied to it. This means that when a force is applied, there is no deformation.

2. **Understanding Non-Rigid Bodies**:
- A non-rigid body, on the other hand, is one that can deform when a force is applied. This means that the distance between points on the body can change.

3. **Analyzing the Steel Balls and Iron Box**:
- In this scenario, we have steel balls inside an iron box. Both the steel balls and the iron box are made of solid materials, which are generally considered rigid bodies.

4. **Behavior of Steel Balls in the Iron Box**:
- When the steel balls are placed inside the iron box, they can move around freely. If we apply force to the box, the balls may shift position, indicating that they are not fixed in place.

5. **Conclusion**:
- Since the steel balls can move and the distance between them can change when a force is applied, they behave like a non-rigid body. Although both the steel balls and the iron box are rigid materials, the system as a whole does not behave as a rigid body because the balls can shift and deform the arrangement.

### Final Answer:
The steel balls in the iron box will behave like a non-rigid body because they can move and change their positions relative to each other when a force is applied.

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