Trigonometry - Bearings (compass and true).
Test Yourself 1.
Conversions from compass to true bearings. | 1. Convert the following compass bearings to true bearings: | |
(i) South
(ii) West (iii) North west (iv) North east. |
(v) North north east (NNE)
(vi) West south west (vii) East 25° south (viii) West 15° north |
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Conversions from true to compass bearings. | 2. Convert the following true bearings to compass bearings: | |
(i) 0° T. (ii) 270° T. (iii) 135° T. (iv) 020° T. |
(v) 210° T. (vi) 310° T. (vii) 157.5°. (viii) 202.5°. |
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Bearings "looking back" FROM | 3. The compass bearing of Point A from Point B is N38°E.
Answer.Bearing of B is S38°W from A or W52°S. |
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4. A ship sails from Point A at a bearing of 090° to point B. It then changes bearing and sails along a course at 240°. What will be the bearing of the ship from point A when the ship travelling on its new course is at its closest distance to point A? Answer.Bearing of 150° from A. |
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5. The compass bearing of A from B is S42°E.
What is the compass bearing from B to A? Answer.Bearing from B to A is N42°W or W48°N. |
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Bearings in right angle triangles. | 7. A ship travels 150 km in a north 40° west direction.
Answer.(i)North: 115 km. (ii) West: 96 km. |
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Bearings with other rules. | 11. A ship S sails from port P on a bearing of N 60° E for 56 kms.
Another ship A also leaves port P but on a bearing 110° T for 48 kms.
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12. Three ships start from Port O.
Answer.(ii) AB = 72 nm. (ii) Bearing of C from B is 338°T. |
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13. The diagram below shows three towns, A, W and B. A plane travelling from town A to town B must make a stop-over at town W. Town W is 120 km on a true bearing of 312° from town A. Town B, which is directly north of town A, is on a true bearing of 042° from town W.
Answer.(ii) 253 - 179 = 74 km. |
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14. A course for a Championship Drone event requires competitors to fly from point A on a bearing of 050° for 1.2 km over cliffs with significant updrafts to point B. From point B they must then fly on a bearing of 230° over land for 2.8 km to point C.
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15. I am looking at Curl Curl beach from a headland. I know that the beach faces east south-east and I draw a small sketch as shown below. | ||
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Answer.(i) True bearing is 112.5°. (ii) Bearing to me FROM beach is 22.5°. (iii) Bearing of Beach from me is 202.5°T or S22.5°W. which is SSW. |
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