Final answer:
The correct temperature setting for thermal curling is determined by the specific heat of iron and depends on the individual's hair type and desired curl intensity.
Step-by-step explanation:
The correct temperature setting of the iron for thermal curling is determined by the specific heat of iron. The specific heat of a substance determines how much heat energy it can absorb or release.
In this case, the iron needs to reach a temperature that is hot enough to curl the hair but not so hot that it damages it.
When curling hair, it is typically recommended to use a temperature setting between 300°F to 400°F (150°C to 200°C) for fine to normal hair, and a slightly higher temperature for thick or coarse hair.
It's important to note that different irons may have different temperature settings, so it's always best to refer to the manufacturer's guidelines.
Ultimately, the correct temperature setting for thermal curling depends on the individual's hair type and the desired curl intensity. It's always a good idea to start with a lower temperature and gradually increase as needed, to avoid damaging the hair.