PROBLEM SET No.3

Due April 6th, 2001, 17.00hr

Problem 1

6-1 A transit was set up over point A and the bearings of lines AB and AC were read and recorded. From these bearings, the angle CAB was computed. Later, it was ascertained that there was a local attraction at point A when the two bearings were read. The local attraction caused the needle to deflect 2⁰ 30' clockwise. What would be the effect of the local attraction on the angle CAB?

Problem 2

The true bearing of a line is N5⁰ 00'W. If the declination is 2⁰ 15'W, what bearing should be used to retrace the line in the field?

Problem 3

The magnetic bearing of a line is due east, and the declination is 2⁰ 30'E. What is the true bearing of the line?

Problem 4 - 6

In problems 4 through 6, what magnetic bearing would be used to retrace the line today?

Problem	Line	Magnetic Bearing	Declination	Declination
		1910	1910	Today
4	A –B	S25⁰ 30'W	5⁰ 30'E	2⁰ 15'E
5	R –S	N16⁰ 15'W	2⁰ 45'W	4⁰ 00'W
6	Y - Z	S82⁰00'E	1⁰ 15'W	2⁰ 00'E

Problem 7

A line is run from A to B, B to C, and C to D. At B, a deflection angle of 10⁰ 06' R is read, defining the direction of BC. At C, a deflection angle of 94⁰ 10'L is read, defining the direction of CD. If the true bearing of AB is known to be S10⁰ 15'W, compute the true bearing of BC and of CD.