Page 190 - 9 teachers social book 9 @ 2077 ctp_Neat

Example II
It is 3:15 in Zurich at 90°E longitude, find the longitude of Poselo where the
time is 10:40 AM.

Solution

The difference in time (12:00 + 3:15)- 10:40 = 4 hours 35 minutes
Changing into minutes 4 × 60 = 240 m + 35 = 275 minutes
275
Changing to degree =
4
= 68°3 |
Since the time in Poselo is behind Zurich it must lie to the west of Poselo
|
|
= 90°E- 68°3 = 23°1 E
Activity

Draw a model of globe and show the International Date Line and discuss its importance.

Exercise

Answer the following questions:

1. Define longitude.
2. Draw a picture of longitudinal lines and show Prime Meridian and International
Date Line.
3. Why do you change the time in your water when you go to London from
Kathmandu and when you go to London from Kathmandu and to Beijing from
Kathmandu?
4. What do you know by IDL? Why is it drawn in a zigzag shape?
5. A person flying to 5AM Francisco from Kathmandu crossing the IDL gains a
day, but his/her friend flying to Kathmandu from the same place crossing the
line loses one day. Why?

Community Work

Suppose you are in Kathmandu. Your uncle is living in Kakarvitta and Aunty is in
Nepalgunj.
Now, ask them to send the time of sunrise in both the places and compare the time
difference of both the places with Kathmandu.

Dynamic Social Studies - Book IX 190