to produce a heat source to demonstrate frictional forces to create a magnetic field to generate a sound wave
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Wire was looped several times around an iron nail, and the wire's ends were connected to a battery. For which of these will this device most likely be used?
Possibilities:
- to produce a heat source
- to demonstrate frictional forces
- to create a magnetic field
- to generate a sound wave

to create a magnetic field