What is a characteristic of iron core transformers compared to air core transformers?

Iron core transformers are designed with an iron core to enhance the magnetic field's efficiency. This core material is crucial in creating a closed magnetic path, which significantly improves magnetic coupling between the primary and secondary coils. The improved magnetic coupling results in better efficiency and performance, allowing these transformers to transfer electrical energy more effectively.

The other characteristics, while they may apply to specific types of transformers or scenarios, do not accurately reflect the benefits of iron core transformers in comparison to air core transformers. For instance, iron core transformers are typically heavier due to the iron material, and while they can manage higher voltages, this is more of a function of the design rather than a distinct characteristic compared to air core transformers. The focus on enhanced magnetic coupling provides a clear distinction, highlighting the superior efficiency of iron core transformers in energy transfer.