Question
A student conducts an investigation to demonstrate how a magnetic field affects objects around it. The student designs an electromagnet as shown in the diagram.
battery - wire coil-01.png
The student rolls a steel ball near the electromagnet and observes that the sphere curves slightly toward the electromagnet. The student wants to revise the electromagnet, so the sphere curves even closer to the electromagnet. Which change would best help the student achieve this result?
Reverse the direction of the battery.
Increase the number of coils of wire.
Add a resistor between the battery and nail.
Replace the nail with one made out of aluminum.
battery - wire coil-01.png
The student rolls a steel ball near the electromagnet and observes that the sphere curves slightly toward the electromagnet. The student wants to revise the electromagnet, so the sphere curves even closer to the electromagnet. Which change would best help the student achieve this result?
Reverse the direction of the battery.
Increase the number of coils of wire.
Add a resistor between the battery and nail.
Replace the nail with one made out of aluminum.
Answers
GPT-4o mini
To help the steel ball curve even closer to the electromagnet, the best change for the student to make would be to **increase the number of coils of wire**.
Increasing the number of coils will strengthen the magnetic field produced by the electromagnet, thus exerting a greater magnetic force on the steel ball, which will cause it to curve more sharply toward the electromagnet.
The other options would not be as effective:
- Reversing the direction of the battery would not significantly change the magnetic field in terms of its strength.
- Adding a resistor would likely reduce the current through the wire, weakening the magnetic field.
- Replacing the nail with aluminum would not work well since aluminum is not ferromagnetic and would not enhance the magnetic field as the steel would.
Therefore, increasing the number of coils is the best option.
Increasing the number of coils will strengthen the magnetic field produced by the electromagnet, thus exerting a greater magnetic force on the steel ball, which will cause it to curve more sharply toward the electromagnet.
The other options would not be as effective:
- Reversing the direction of the battery would not significantly change the magnetic field in terms of its strength.
- Adding a resistor would likely reduce the current through the wire, weakening the magnetic field.
- Replacing the nail with aluminum would not work well since aluminum is not ferromagnetic and would not enhance the magnetic field as the steel would.
Therefore, increasing the number of coils is the best option.