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Trig Bearings C2

Hi

I'm doing Chapter 17 in C2 at the moment,and am stuck with a couple of questions.
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I've only ever encountered simple bearings calculations before,as I only did Scottish Standard Grades,not GCSEs. I don't find the calculations hard, I'm simply not sure how to draw the diagrams out. If anyone could help me out with the diagrams on these questions and explain them,that'd be fantastic.

1)A motorist travelling along a straight level road in the direction 053 degrees observes a pylon on a bearing of 037 degrees.800m further along the road the bearing of the pylon is 296 degrees. Calculate the distance of the pylon from the road.

2)A ship rounds a headland by sailing first 4 nautical miles on a course of 069 degrees, then 5 nautical miles on a course of 295 degrees. Calculate the distance and beariing of its new position from its original position.

For 2) I've calculated the distance,but I'm not sure how I would reconstruct the diagram to calculate the new bearing.

3)From a point A,25m due south of a tree,the angle of elevation of the top of the tree is 27 degrees. From a point B the bearing of the tree is 204 degrees and the angle of elevation of its top is 18 degrees. The points A,B and the foot of the tree are on level ground. Find,correct to the nearest 0.1m
(a)the height of the tree
(b)the distance frm B to the foot of the tree
(c)the distance AB

I'm not asking for anyone to do the entire calculations for me. If anyone could just help me with constructing the diagram and possibly post diagrams,it'd be very much appreciated.

Thanks a lot!

(edited 12 years ago)

Reply 1

nuodai

You really just have to draw diagrams of this sort of thing. For (1), for example, you'd be best to draw a triangle, and at each of the three vertices draw an upward arrow (representing North, or

0^o

) and then the angle coming round from it. From such diagrams, it's normally quite clear what you have to do to find the internal angles of the triangle, and hence the lengths of the edges (which represent the distances). If there was an easy way of me drawing it on the computer for you I'd do so, but without a scanner or anything I can't really do that :p:

Reply 2

Ezraeil

nuodai

You really just have to draw diagrams of this sort of thing. For (1), for example, you'd be best to draw a triangle, and at each of the three vertices draw an upward arrow (representing North, or

0^o

Yeah,it's just the diagrams which confuse me,sometimes I wish I could've done GCSEs :mad:

Would make life a bit easier for me,maths-wise anyway :rolleyes:

Reply 3

parfait-ego

look at a gcse maths book and that should give you an idea of the diagrams

Reply 4

bigmansouf

bump is there anyone that can help with the questions i looked at my gcse books but nothing was discussed in depth about elevation of angles
please help

Reply 5

bigmansouf

Can someone point me in the right direction to understand how to approach the angles of elevation and depression.