How is the Earth's surface divided in terms of time zones?

• A. Into 12 vertical sectors
• B. Into 24 vertical sectors
• C. Based on latitude lines
• D. Based on population density

Answer: (B)

The Earth's surface is divided into time zones primarily based on a system of 24 vertical sectors, with each zone roughly corresponding to one hour of the Earth's 24-hour day. As the Earth rotates on its axis, it is divided into these time zones to ensure that local times correspond with the position of the sun in the sky.

Each vertical sector, or time zone, typically spans 15 degrees of longitude because the Earth rotates 360 degrees in about 24 hours, translating to 15 degrees per hour. This organization allows for a uniform understanding of time globally, accommodating the natural cycles of day and night as one moves east or west across the globe.

The other options are not suitable for defining time zones. Latitude lines, for instance, relate primarily to geographical location and climate, and population density does not provide a basis for time division. The concept of 12 vertical sectors would also be insufficient, as it would not accurately reflect the full range of time variation experienced across the globe. Therefore, the division of the Earth's surface into 24 vertical sectors is the most accurate and widely accepted method for organizing time zones.