Map scale

Map Scales Scale: Shows the relationship between the distance on a map and the actual distance on the earth’s surface Ex:1:50,000 means: 1cm on the map = 50 000 cm on the earth There are 3 different types of scale: Direct Statement Scale (1cm = .5 km) Line Scale Representative Fraction (1:50,000) 1cm .5 km

Direct Statement Scale: Types of Scales Direct Statement Scale: Uses words to show the relationship of the scale 1cm to 1km or 1cm=1km

Question??? If you have measured the distance between Hamilton and Toronto and found it to be 25 cm on the map and the direct statement reads 1cm to 2 km. How far would it be in km?

The answer is…. 50 km 1 cm/25cm = 2 km/X 1xX = 2x25 X-50cm

2. Line Scale: Is a ruler that is divided into units of distance 1st measure the distance on the map and 2nd compare it to the scale to calculate the distance

3. Representative Fraction (R.F.): Is usually shown as a ratio 1:50 000 1 unit on the map represents 50 000 of the same units on the earth’s surface

1: 50 000 The 1st term Is always 1 Represents distance on the map Represents same unit of measure as the 2nd term The 2nd term 50 000 represents the distance on the earth Represents same unit of measure as the 1st term First term is always 1 (represents the distance on the map) 50 000 represents the distance on the earths surface Represents the same unit of measurement on both terms of the ratio

Metric Conversions 1 km = 1000m 1 m = 100cm 1km = 100 000 cm Converting R.F. to direct statement - divide by 100 000 (move the decimal 5 places to the left) Example: 1: 50 000 1cm = 50 000cm 1cm= (50 000/100 000)km 1cm= 0.5km

Converting direct statement to R. F Converting direct statement to R.F. - multiply by 100 000 (move decimal 5 places to the right) Example: 1cm to 2.5km 1 cm = (2.5 km x 100 000 cm) 1 cm = 250 000 cm (1: 250 000)

Scale Exercise Direct Statement Representative Fraction Line Scale 1cm to 2.5 km 1: 350 000 0 40 km

Applying Scale… A B - 1cm to 100 km A B - 1: 250 000 0 20 km B- 1 cm