Magnetic compass bowls are filled with a liquid to

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Multiple Choice

Magnetic compass bowls are filled with a liquid to

Damping of the float’s motion is the key idea. The liquid provides viscous resistance as the float and magnetic needle move with the ship’s roll, pitch, and vibrations. This resistance dissipates energy quickly, so the needle settles faster and stays steadier, giving a stable, readable indication even in rough seas. Magnetic sensitivity isn’t improved by the liquid itself—the sensitivity comes from the magnet and the compass card’s geometry. Preventing freezing is not the main purpose, though some liquids have low freezing points. Increasing buoyancy isn’t the primary goal either; the float’s buoyancy is a design choice, while the liquid mainly smooths the motion.

Damping of the float’s motion is the key idea. The liquid provides viscous resistance as the float and magnetic needle move with the ship’s roll, pitch, and vibrations. This resistance dissipates energy quickly, so the needle settles faster and stays steadier, giving a stable, readable indication even in rough seas. Magnetic sensitivity isn’t improved by the liquid itself—the sensitivity comes from the magnet and the compass card’s geometry. Preventing freezing is not the main purpose, though some liquids have low freezing points. Increasing buoyancy isn’t the primary goal either; the float’s buoyancy is a design choice, while the liquid mainly smooths the motion.

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