Question

which would you sprinkle around the electromagnet that you produced in the laboratory activity to see its magnet field lines?
which would you use to determine the direction of the field lines around a magnet?
which would you use with a circuit to determine if a magnet was moving in close proximity to the circuit?

Explanation:

1. To see the magnetic field lines of an electromagnet, iron filings are sprinkled. They align along the field lines due to magnetic forces.
2. A compass (with a magnetic needle) is used to determine the direction of magnetic field lines, as the needle aligns with the field direction.
3. A galvanometer (or a coil in a circuit with a detector) is used to detect induced current when a magnet moves near the circuit (electromagnetic induction), indicating the magnet's motion.

Answer:

1. Iron Filings
2. Compass (Magnetic Needle)
3. Galvanometer (or Circuit with Current Detector)