Chapter 15 Time And Temperature Worksheet Page 14
ADVERTISEMENT
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22288
TIME AND TEMPERATURE (Chapter 15)
F
TIME ZONES
The Earth rotates from west to east about its axis.
This rotation causes day and night.
As the sun rises in the Chinese city of Beijing, India
sun’s
is still in darkness. It is therefore later in the day in
Beijing. By the time the sun rises in India, Beijing
1
rays
has already experienced 2
hours of daylight.
2
TRUE LOCAL TIME
o
The Earth rotates a full 360
every day.
o
This is 360
in 24 hours
o
or 15
in 1 hour
f360 ¥ 24 = 15g
o
1
or 1
in 4 minutes.
f
of 60 min = 4 ming
15
Places on the same
line of longitude
share the same
true
.
local time
North Pole
However, using true local time would cause many
problems.
For example, any movement to the east or west would
mean the time would be different, so the time on one side
lines of
of a city would be different to the time on the other side.
longitude
Some states of the USA and Australia stretch across almost
o
15
of longitude. This would mean time differences of up
South Pole
to one hour within the same state.
The solution to these problems was to create
.
time zones
STANDARD TIME ZONES
The following map shows lines that run between
the North and South Poles. They are not straight
like the lines of longitude but sometimes follow the
borders of countries, states or regions, or natural
boundaries such as rivers and mountains.
o
0
The first line of longitude,
, passes through
Greenwich near London. This first or
prime
12
is the starting point for
time zones
meridian
12
west of Greenwich and
time zones east of
Greenwich.
Places which lie within a time zone share the same standard time. Standard Time Zones are
1
mostly measured in 1 hour units, but there are also some
hour units.
2
Time along the prime meridian is called Greenwich Mean Time (GMT).
ADVERTISEMENT
0 votes
Related Articles
Related forms
Related Categories
Parent category: Education