Which statement best describes how a traditional magnetic compass works?

Which statement best describes how a traditional magnetic compass works?

• A. Laser pointer in sealed bowl
• B. Gyroscopic device that maintains orientation
• C. Magnetized needles fastened to a graduated card, mounted on a pivot permitting free rotation
• D. A GPS-based satellite system

Answer: (C)

A traditional magnetic compass works by a magnetized needle free to rotate on a low-friction pivot, so it aligns with the Earth's magnetic field. The horizontal component of that field exerts torque on the needle, pulling it until it points toward magnetic north. The graduated compass card attached to the needle lets you read directions as the needle settles. This setup is distinct from other systems: a laser pointer in a sealed bowl isn’t a navigation reference, a gyroscopic device describes a gyrocompass that maintains orientation without relying on Earth’s field, and GPS relies on satellite signals rather than a magnetic field. Remember, the compass points to magnetic north, which may require adjusting for magnetic declination to find true north.

A traditional magnetic compass works by a magnetized needle free to rotate on a low-friction pivot, so it aligns with the Earth's magnetic field. The horizontal component of that field exerts torque on the needle, pulling it until it points toward magnetic north. The graduated compass card attached to the needle lets you read directions as the needle settles. This setup is distinct from other systems: a laser pointer in a sealed bowl isn’t a navigation reference, a gyroscopic device describes a gyrocompass that maintains orientation without relying on Earth’s field, and GPS relies on satellite signals rather than a magnetic field. Remember, the compass points to magnetic north, which may require adjusting for magnetic declination to find true north.