Question

question: electric motors that operate refrigerators, vacuum cleaners, and washing machines use which devices to create a temporary magnetic field? answer options: select one of four compass needles keepers electromagnets iron filings

Explanation:

To determine the device used to create a temporary magnetic field in electric motors of appliances like refrigerators, vacuum cleaners, and washing machines, we analyze each option:

• Compass needles are used for direction (magnetic north) and don't create a temporary magnetic field for motors.
• Keepers are used to preserve the magnetism of permanent magnets, not create temporary fields for motors.
• Electromagnets create a magnetic field when an electric current passes through them and lose it when the current stops, which is ideal for temporary magnetic fields in electric motors.
• Iron filings are used to visualize magnetic fields, not create them for motor operation.

Answer:

Electromagnets