What is meant by poor conductors of heat (or insulators of heat) ? Give two examples of materials which are poor conductors of heat (or insulators).

Explanation

### Step-by-Step Solution:

1. **Definition of Poor Conductors of Heat**:
Poor conductors of heat, also known as insulators, are materials that do not allow heat to pass through them easily. This means that when heat is applied to one side of the material, it does not quickly transfer to the other side.

2. **Explanation through Experiment**:
To illustrate this concept, consider an experiment with two beakers containing the same amount of water (1 liter each). One beaker is made of steel, and the other is made of glass. When heat is applied to both beakers from the bottom, the steel beaker heats the water to 100 degrees Celsius in about 5 minutes, while the glass beaker takes approximately 9 minutes to reach the same temperature.

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