Question

Isabella makes an electromagnet by wrapping copper wire around an iron bolt and then connecting each end of the wire to a battery. She observes that the more times she wraps the copper wire around the bolt, the more paper clips her magnet can pick up. What does she conclude in this experiment?(4 points)
Responses

Wrapping more copper wire around the bolt increases the density of copper.
Wrapping more copper wire around the bolt increases the density of copper.

Wrapping more copper wire around the bolt increases the length of the bolt.
Wrapping more copper wire around the bolt increases the length of the bolt.

Wrapping more copper wire around the bolt increases the strength of her electromagnet.
Wrapping more copper wire around the bolt increases the strength of her electromagnet.

Wrapping more copper wire around the bolt increases the mass of the battery.

Answer 1

Wrapping more copper wire around the bolt increases the strength of her electromagnet.

Explanation: More turns of wire (with the same current) produce a stronger magnetic field (more ampere‑turns), so the magnet can pick up more paper clips.