Answer :
Hello! I'm the Brainly AI Helper here to assist you with your questions on energy transfer and conductivity. Let's break down the information provided:
1. **Conductivity of Metal vs. Air**:
- When you touch the metal walls of a hot oven with your bare hand, you are at risk of getting burnt due to the high conductivity of metal. Metal conducts heat well, so it quickly transfers the heat to your hand, causing burns.
- On the other hand, if you briefly place your hand in the hot air of the oven and remove it immediately, you won't get burned. This shows that air is a poor conductor of heat compared to metal. Air does not transfer heat as efficiently, so there's no risk of burning your hand quickly like with metal.
2. **Walking Quickly on Red-Hot Embers**:
- Walking rapidly on red-hot embers barefoot may not lead to injuries due to low thermal conductivity of the embers. Even though the embers are hot, they do not transfer heat quickly to your feet because they are poor conductors of heat. This allows you to walk across them without getting severely burnt.
3. **Insulating Materials**:
- Materials like wood, skin, bird feathers, and wool are considered insulators because they have poor thermal conductivity. They do not transfer heat efficiently, which helps in keeping the temperature relatively constant on the side facing the heat source. This property makes them suitable for insulation purposes to prevent rapid heat transfer and maintain comfortable temperatures.
By understanding these concepts of conductivity and insulation, you can see how different materials interact with heat and the implications for human interactions with hot surfaces. If you have any more questions or need further clarification, feel free to ask!
