10-35.
To detect accidental movement when
measuring a number of horizontal
angles from one setup, you should
take which of the following steps?
1.
Relevel the instrument and
check the readings
occasionally
2.
Adjust the instrument before
and after each reading
3.
Train the instrument at some
clearly defined object to
serve as a reference mark for
checking the sizes of the
angles
4.
Take the mean of the observed
angles
10-36.
The closing-the-horizon method of
checking the accuracy of angular
measurements is based on the
geometrical fact that the sum of
the
1.
angles in a triangle are 180°
2.
angles around a point are 360°
3.
acute angles in a right
triangle are 90°
4.
interior angles of a closed
five-course traverse are 540°
10-37.
A vertical angle was recorded at
+36°.
This angle is a measurement
of what type?
10-38.
1.
Inclination
2.
Declination
3.
Depression
4.
Elevation
You are measuring a 30° angle with
a 1-minute transit.
To improve
the precision of this measurement,
you turn the angle a total of four
times.
If the plate reading after
the fourth measurement is 119°59°,
what is the size of the angle
turned?
1.
29°45’45”
2.
29°59’45”
3.
30°00’15”
4.
30°45’15”
10-39.
You have measured an angle using
the repetition procedure.
If the
original measurement was 37°22’
and your sixth and last repeat was
224°12’42”, what is the mean
angle?
10-40.
Which of the following procedures
is a method for extending a
straight line?
1.
Repeating angles
2.
Averaging sets of backsight
points
3.
Double centering
4.
Jiggling in
10-41.
What step in the double-centering
procedure is taken just before the
instrument is rotated through 180°
in the horizontal plane?
1.
Plunging the telescope
2.
Taking the first foresight
3.
Taking the backsight
4.
Taking the second foresight
10-42.
When double centering results in
two different extension points,
what procedure should you use?
1.
2.
3.
4.
Extend your line through the
first point
Extend your line through the
second point
Extend your line through a
point midway between the two
extension points
Ignore both points and start
over again
1.
37°5’7”
2.
37°22’7”
3.
37°10’20”
4.
38°00’57”
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