1. ©G Dear2008 – Not to be sold/Free to use
Stage 5
Years 9 & 10
Compass &
True Bearings
Bearings
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©G Dear2008 – Not to be sold/Free to use

2. Bearing (1/4) Bearings are used to describe direction.
Compass bearings have four main directions NW NE
and four middle
directions W E SW SE
True Bearings are more specific, using a 3-digit angle clockwise from North. S
Practice 1
Practice 2
Practice 3
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3. Bearing Ex 1 (2/4) A. .L .B Ship A is 17km west of a lighthouse L. N
Ship B is due south of the lighthouse L.
Ship B is SE of ship A.
Calculate distance d from Ship A to ship B. A.
17 km .L
45o 17 d
Cos 45o = d
d = 17 ÷ Cos 45o .B
≈ 24 km 3

4. A Ship sails for 20 km on a bearing of 130o.
Bearing Ex 2 (3/4)
A Ship sails for 20 km on a bearing of 130o.
How far south is the ship from its starting point?
130o
50o d
20 km d 20
Cos 50o =
d = 20 x Cos 50o
≈ 12.9 km 4

5. Find Mary’s bearing from her starting position.
Bearing Ex 3 (4/4)
Mary walks 3.4 km east
, then 1.3 km south.
Find Mary’s bearing from her starting position.
90o
3.4 km θo
1.3
3.4
Tan θo =
1.3 km
Tan-1 ( )
1.3
3.4
θo =
≈ 21o
Bearing = 90o + 21o
= 111o 5