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無投影片標題 - IT in Education

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					Locating Places on Maps -Grid Reference (格網座標)

Look at the relief map of H.K. Can you tell the location of Tai Mo Shan

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Look at the seating plan of your classroom Can you tell the location of Carol’s seat in the classroom?

What is grid reference?

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•A grid is a set of numbered vertical and horizontal lines which cross each other.
•Grid reference is a number which represents the location of a place on a grid.

Naming grid lines on maps

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Map 1

•The vertical lines are numbered from west to east. The vertical lines are called eastings (東行線). •The horizontal lines are numbered from south to north. The horizontal lines are called northings (北行線).

How to read a grid reference?
•Grid reference is formed by the intersection of an easting and a northing. •To tell the position of a place, we put the easting first and then northing.

Example: The 4 - figure grid reference (grid square) of pig farm 3 is 1324
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Exercise 1: Complete the table.
Location Easting Northing Grid reference (4-figure)

Pig Farm 1 and 2 Ah jing’s home
Factory A Factory B

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1224
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Exercise 2: Draw the following things on the map 1

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Sometimes, a 4 - figure grid reference does not give the exact location of a place. For example, on Map 1, both pig farm 1 and 2 are on the grid square 1224. It does not tell us the exact location of the pig farm 1and 2. To be more exact, we use a 6 - grid reference.

To do this, we divide each grid square into ten smaller squares numbered from 1 to 9.

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Example: The 6 - figure grid reference of pig farm 1 is 125245 pig farm 2 is 129 244

Exercise 3:
Give a 6 - figure grid reference for each of these on Map 2.

129240 Railway station _______________
fire station ___________ 131243 hospital _____________ 137241

127245 police station_____________ 127237 church ________________ 131219 cultivated land __________

Why do we use grid references?

•Grid reference make it quick and easy to locate places on maps. •They also make it easier to tell someone else where something is.

The End

EDD 5161b Group 9
Prepared by : Lee Mei Ling 96010140 Chung Mei Yin 96010550 Leven Wong 97029110


				
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