A student wraps 10 coils of copper wire around an iron bolt, and then she connects the ends of the wire to a battery. Next, the student uses the nail to lift paper clips. She then conducts a second trial using the same wire, battery, and nail, but with 30 coils of copper wire wrapped around the bolt. What will happen in the second trial?

Question

option:

The bolt will lift less paper clips, because more conductive material in the system will balance more paper clips.
The bolt will lift less paper clips, because more conductive material in the system will balance more paper clips.

The bolt will lift more paper clips, because more coils of wire produces a stronger magnetic field.
The bolt will lift more paper clips, because more coils of wire produces a stronger magnetic field.

The bolt will lift the same number of paper clips, because both trials used the same type of paper clips.
The bolt will lift the same number of paper clips, because both trials used the same type of paper clips.

The bolt will lift the same number of paper clips, because both trials used the same type of battery.

Answer 1

The correct option is:

The bolt will lift more paper clips, because more coils of wire produces a stronger magnetic field.

In an electromagnet, the strength of the magnetic field is proportional to the number of coils of wire around the core. By increasing the number of coils from 10 to 30, the student enhances the magnetic field generated when current flows through the wire, resulting in a greater lifting capacity for the paper clips.