Navigational instrument with compasses - Quiz #10

The Earth’s magnetic field is primarily generated by:

• Ferromagnetic materials in the crust

• Convection currents in the outer core

• Solar wind interacting with the ionosphere

• Permanent alignment of mantle minerals

Magnetic inclination (dip) is zero at:

• Magnetic poles

• Geographic equator

• Magnetic equator

• 45° latitude

A ship’s magnetic signature causing deviation is classified as:

• Permanent, induced, and variable

• Only permanent and induced

• Only variable due to cargo

• Unaffected by ship’s heading

Quadrantal deviation is maximum on headings of:

• 000°, 090°, 180°, 270°

• 045°, 135°, 225°, 315°

• 030°, 120°, 210°, 300°

• 060°, 150°, 240°, 330°

A Flinders bar compensates for:

After degaussing, a compass must be:

• Replaced immediately

• Re-adjusted using correctors

• Used only in equatorial regions

• Ignored unless deviation exceeds 10°

A compass with a deviation table showing +4°E on 090° and -2°W on 270° indicates:

• Symmetrical fore-and-aft magnetism

• Asymmetrical athwartships magnetism

• Pure quadrantal deviation

• Instrumental error

Heeling error is corrected by:

• Spherical soft iron correctors

• Vertical permanent magnets

• Adjusting Flinders bar length

• Increasing compass height

In the Baltic Sea (high latitude), your compass needle drags. The first action is:

• Reverse polarity of heeling magnet

• Check for induced magnetism in deck cranes

• Ignore it—dip error is normal here

• Switch to GPS immediately

After loading steel coils, your compass deviation increases unpredictably. This is caused by:

• Permanent magnetism changes

• Induced magnetism in vertical soft iron

• Quadrantal deviation shifts

• Solar storm interference