Important Questions Class 8 Chapter 1 Geography Maharashtra Board

Imp Questions For All Chapters – Geography Class 8

Local Time and Standard Time

Short Questions

1. What is local time?

• Local time is the time of a place based on the position of the Sun in the sky.

2. How many degrees does the Earth rotate in one hour?

• The Earth rotates 15° in one hour.

3. What is the standard meridian of India?

• The standard meridian of India is 82.5°E longitude, passing through Mirzapur, Uttar Pradesh.

4. How many time zones are there in the world?

• There are 24 time zones, each covering 15° longitude.

5. Why do some countries have multiple time zones?

• Large countries like USA, Canada, and Russia span multiple longitudes, requiring multiple time zones.

6. What is the time difference between IST and GMT?

• Indian Standard Time (IST) is 5 hours 30 minutes ahead of Greenwich Mean Time (GMT).

7. What is the International Date Line (IDL)?

• The IDL is at 180° longitude and helps adjust the date when crossing time zones.

8. What happens when we travel east across the International Date Line?

• We lose a day, meaning the date moves back by one day.

9. Why was Greenwich chosen as the Prime Meridian?

• Greenwich was chosen because it was a major center for navigation and timekeeping.

10. How many standard time zones does Canada have?

• Canada has 6 different standard time zones.

Long Questions

1. What is the difference between local time and standard time?

• Local time is determined by the position of the Sun, which changes for every longitude. Standard time is the official time set for a region, usually based on a central meridian, to avoid confusion.

2. Why is IST taken from 82.5°E longitude?

• India has multiple longitudes, so 82.5°E was chosen as the central meridian to maintain a uniform time across the country. This helps in synchronizing activities across different states.

3. What is Greenwich Mean Time (GMT), and why is it important?

• GMT is the time at 0° longitude (Prime Meridian), used as a reference for world time zones. It is important for global communication, navigation, and standardizing international timekeeping.

4. Why do we need time zones?

• Since the Earth rotates, different places experience day and night at different times. Time zones help people in different regions follow a uniform time system for work, travel, and communication.

5. How is the International Date Line used to adjust dates?

• The IDL at 180° longitude helps adjust dates when crossing time zones. Moving east across the line means losing a day, while moving west adds a day to the calendar.

6. How is time calculated for different longitudes?

• Time is calculated based on the formula: Time Difference (minutes) = Longitude Difference × 4 minutes. Each 15° longitude difference creates a 1-hour time change.

7. What would be the local time at 30°W if it is 12 noon at 60°E?

• The longitude difference is 90° (60°E to 30°W). Since each degree equals 4 minutes, the total difference is 6 hours. So, the time at 30°W would be 6:00 AM.

8. Why does Russia have 11 time zones?

• Russia is a vast country covering over 165° of longitude, so to manage time effectively, it follows 11 different time zones to match the natural daylight cycle in different regions.

9. What is the difference between UTC and GMT?

• GMT is based on the Prime Meridian’s solar time, while UTC (Coordinated Universal Time) is based on atomic clocks for accuracy. UTC is now the global standard for timekeeping.

10. Why does the USA have different time zones?

• The USA spans 4 major time zones (Eastern, Central, Mountain, and Pacific) because it extends across a wide area. This ensures that each region follows a time that matches its daylight hours.