A ship is sailing from the International Date Line on Wednesday, from East to West (from America to Russia). What will happen to…

Question

A ship is sailing from the International Date Line on Wednesday, from East to West (from America to Russia). What will happen to the day or date on the ship?

1. A. Date will remain Wednesday (same day)
2. B. Date will change to Tuesday (one day back)
3. C. Date will change to Thursday (one day forward). (Correct answer)
4. D. Day remains the same, only the time changes.

Correct Answer

Option C — Date will change to Thursday (one day forward).

Detailed Solution & Explanation

The correct answer is Date will change to Thursday (one day forward).

Key Points

• The International Date Line (IDL) runs roughly along the 180° meridian in the Pacific Ocean, deviating around island groups so that no inhabited territory is split between two dates.
• The rule for crossing it:
  • Crossing from east to west — as from America to Russia — the traveller gains a day, so one day is added.
  • Crossing from west to east — from Asia towards America — the traveller loses a day, so one day is subtracted.
• Sailing east to west on a Wednesday, the date therefore advances to Thursday.

Additional Information

• Why the line is necessary: the Earth rotates 360° in 24 hours, so each 15° of longitude equals one hour and each 1° equals 4 minutes. Travelling right around the globe accumulates a full 24-hour discrepancy, and the Date Line is where that discrepancy is corrected.
• Memory aid: going west, you are travelling *against* the direction of the Sun's apparent motion and moving *ahead* in calendar terms — west, add. Going east, subtract.
• The Prime Meridian (0°) passes through Greenwich, London, and is the reference for Greenwich Mean Time (GMT). The IDL sits on the opposite side of the globe at 180° precisely so that the date change occurs in the sparsely inhabited mid-Pacific.
• Indian Standard Time is based on 82°30′ E, passing near Mirzapur in Uttar Pradesh, giving IST = GMT + 5:30. India uses a single time zone despite spanning about 30° of longitude, which amounts to roughly two hours of solar time between Gujarat and Arunachal Pradesh.
• The line is not perfectly straight — it bends east around Kiribati and west around the Aleutians and Chukotka, so that political units remain on a single date.