Geography Paper 3 WASSCE (PC), 2019

Question 3
(a) Define longitude.
(b) State three characteristics of longitude
(c) Find the time in Town Z (75° E) when the time in town B (20° E) is 6.00 pm.

Observation

 

This question was attempted by few candidates and their performance was a bit above average in all parts of the question. The answers that were required of the candidates were:

(a) Definition of longitude
It is an imaginary line on the Earth’s surface running from North Pole to South Pole.
OR
It is an angular distance measured from the centre of the Earth, east or west of the Greenwich Meridian.

(b) Characteristics of longitude
- they are imaginary lines
- run from North Pole to South Pole on the globe
- also called meridians
- run at right angle to the latitudes
- places on same longitude have same local time
- all longitudes meet at the poles
- measured in degrees from centre of the earth
- measured east or west of Greenwich Meridian
- the central longitude is the Greenwich Meridian
- most important longitudes are 00 and 1800
- they have the same length
- spacing is widest at the equator and decreases pole wards
- they are numbered from 00 to 1800 east and west
- longitude 1800E and 1800E are a single longitude
- opposite longitudes pair up to form Great Circles
- it is used to calculate local time
- time difference between two longitudes that are 10 apart is 4 minutes
- divides the world into time zones

(c) Calculation of mere listing = 1 mark each Time in town Z
Town B = 200E
Local Time at B = 6.00pm
Town Z = 750E
Difference in longitude = 75ᵒ - 20ᵒ = 55ᵒ
For every 1ᵒ = 4 min or 150 = 1 hour
55ᵒ = 55 x 4 min = 220 min

Town Z is east of Town B
Time at Z is ahead of Time at B
Time at Z = 6.00pm + 3 hrs 40 mins = 9.40 pm