I student wraps copper wire around an iron nail. Then she connects the ends of the wire to a battery, making an electromagnet. She notices that if she wraps more coils of wire around the boat, then her electromagnet can pick up more paper clips. What conclusion can she draw?A. More coils of wire increases the mass of the battery.B. More coils of wire increases the density of the copper wire.C. More coils of wire increases the length of the nail.d. More coils of wire increases the strength of electromagnet.
D. More coils of wire increases the strength of the electromagnet.
The number of coils around the iron nail is directly related to the strength of the magnetic field that is created when an electric current passes through the wire. More turns in the coil result in a stronger magnetic field, which increases the electromagnet's ability to attract ferromagnetic objects like paper clips. The mass of the battery, the density of the copper wire, and the length of the nail are not affected by the number of coils wrapped around it.