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Refer to the hiking trail in blocks A5 and B5 on the topographic map - NSC Geography - Question 2 - 2020 - Paper 2
Question 2
Refer to the hiking trail in blocks A5 and B5 on the topographic map. 2.1.1 Determine the 2020 magnetic bearing (MB) of the hiking trail from M to N in blocks A5 an... show full transcript
Worked Solution & Example Answer:Refer to the hiking trail in blocks A5 and B5 on the topographic map - NSC Geography - Question 2 - 2020 - Paper 2
Step 1
Determine the 2020 magnetic bearing (MB)
Answer
To find the magnetic bearing (MB), we will use the formula:
Where:
- True Bearing (TB) = 333° (Assumed from the context of the question)
- Magnetic Declination (MD) = 17°40' west of true north, which is negative in this context.
Calculating MB:
Thus, the 2020 magnetic bearing of the hiking trail is approximately 315.3°.
Step 2
Explain why it is important to use the magnetic bearing instead of the true bearing
Answer
Using magnetic bearing is crucial for navigation in topographic maps for the following reasons:
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Accuracy: The true bearing can vary with the magnetic declination which changes annually due to shifts in the Earth's magnetic field. Hence, using magnetic bearings ensures that navigation is aligned with actual magnetic north.
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Obstruction Avoidance: If the true bearing is used, the desired destination may not be reached, leading to possible obstructions or misdirection. This makes magnetic bearings a more reliable option for accurate navigation in the field.