Name any two machines in which bearings are used.

Explanation

**Step-by-Step Solution:**

1. **Understanding Ball Bearings**:
- Ball bearings are mechanical components that help reduce friction between moving parts. They allow for smooth rotation and movement by providing a low-friction interface.

2. **Identifying Machines that Use Ball Bearings**:
- To answer the question, we need to think of machines where ball bearings are essential for their operation.

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