Q 01/05

The International Date Line runs mostly through which ocean?

A) Pacific

B) Atlantic

C) Indian

D) Arctic

Answer · why

A) Pacific

Pacific: the line runs from pole to pole but mostly crosses the Pacific, which Magellan reportedly named 'peaceful' for the calm water he found after ...

Q 02/05

Which line of longitude does the International Date Line roughly follow?

A) 0°

B) 45°

C) 90°

D) 180°

Answer · why

D) 180°

180°, though the line zigzags east and west of that meridian so that island groups and territories each keep a single calendar date.

Q 03/05

What happens to the calendar date when you cross the date line travelling eastbound?

A) It goes forward one day

B) It stays the same

C) It goes forward one hour

D) It goes back one day

Answer · why

D) It goes back one day

It goes back one day: an eastbound traveller turns the calendar back at the line and so lives through part of that date a second time.

Q 04/05

Legally, what kind of line is the International Date Line?

A) A treaty boundary

B) A UN-mandated line

C) A cartographic convention

D) An IMO shipping rule

Answer · why

C) A cartographic convention

A cartographic convention: no treaty or international body fixes the line, so the countries it passes near are free to choose which date they keep.

Q 05/05

Travelling westward around the world, how must you set your clock for every 15° of longitude crossed?

A) Back one hour

B) Forward one hour

C) Forward 15 minutes

D) Back 24 hours

Answer · why

A) Back one hour

Back one hour: solar noon shifts four minutes for every degree of longitude, so a place 15° farther west reaches noon an hour later.