Answer Key: Self-Test B-1.3
- b. Horizontal levelling only
- c. An automatic level
- d. The automatic level
- a. Optical and laser
- d. Laser levels need only one person to operate them
- c. An automatic level
- c. Four
- a. A second eyepiece
- d. An infrared beam
- a. Crosshairs and stadia lines
- Focus knob (screw)
- Sunshade
- Tilting or split-bubble knob (screw)
- Horizontal (azimuth) slow motion knob (screw)
- Horizontal (azimuth) lock
- Levelling thumbscrew (pin)
- Tripod headplate
- Eyepiece
- Footplate
- a. At the eyepiece
- d. By turning the focus screw located on the barrel
- a. The horizontal clamp is tightened
- d. By a 5⁄8″ NC female thread connection
- b. A split bubble
- b. Azimuth screw
- d. To measure distance
- c. A Philadelphia rod
- b. Metric and imperial
- b. Engineer’s scales are in feet and decimal feet, just like imperial elevations
- c. 49.60 ft 4.357′ – 3.861′ = 0.496′; 0.496 × 100 = 49.60′
- b. 10 mm or 1 cm
- a. Each black mark is 1⁄8″ in width, as well as the white space between marks
- c. 0.01 ft
- a. Pointed graduations (marks)
- c. Rod, target or pencil up
- c. To ensure that the rod is plumb. The lowest reading is the one that is desired.
- a. If soft rubber feet or suction cups aren’t available, use a triangle fashioned out of 1×4’s
- c. The direction of the left thumb determines the direction that the bubble will move
- c. The prism in the automatic level does the fine-tuning
- c. If the unfolded tripod is set at chin level, the eyepiece will be at a comfortable height
- a. With one leg uphill, the other two downhill for a more stable base
- c. Snugged up but not over tightened
- d. An engineer’s (tilting, split bubble) level needs to be fine-levelled for each sight
- a. A tubular level vial
- 30 × 2 = 60 metres apart in total
- b. 6 mm or ¼” over 30 metres or 100 feet
- a. Taken off the tripod and stored in its case
- d. Make sure it fits properly and doesn’t jam parts when trying to close the lid of the case
- a. By its base. This is the strongest part of the instrument
- d. This is the best choice given. Never rub a lens with anything other than a camel hair brush
- d. Once dry, use a camel hair brush on the dry lens in a circular motion
- b. Could cause the interior lens to fog up
- d. This way, if you trip and fall forward, only the tripod feet hit the ground
- c. This way, the instrument is never out of sight and less likely to be damaged
- a. True
- a. True, the tubular level vial expands and the bubble is harder to centre
- c. 100.00 feet is used, as residential plans are normally in imperial scale
- b. Backsights determine the height of the instrument
- a. The rim of a manhole is a stable and long-lasting item, suitable for use as a benchmark
- d. Scotchlite or reflective facing is easier to see in low light conditions
- d. 2.792 m
- a. 0.978 m
- c. 2.410 m
- b. Benchmark of 100.000 m + BS reading of 1.321m = 101.321 m
- a. HI 101.321 – FS reading of 2.118 m = 99.203
| STA | BS | HI | IFS | FS | ELEV |
|---|---|---|---|---|---|
| BM | 1.610 | 101.610 | 100.000 m | ||
| A | 101.610 | 3.555 | 98.055 | ||
| B | 101.610 | 1.615 | 99.995 | ||
| C | 101.610 | 1.547 | 100.063 | ||
| C | 1.341 | 101.404 | 100.063 | ||
| D | 101.404 | <0.540> | 101.944 | ||
| E | 101.404 | 2.902 | 98.502 | ||
| F | 101.404 | 104.149 | |||
| F | <2.129> | 102.020 | <2.745> | 104.149 | |
| G | 102.020 | 1.798> | 103.818 | ||
| H | 102.020 | 1.030 | 100.990 | ||
| I | 102.020 | 3.345 | 98.675 | ||
| J | 102.020 | <0.299> | 102.319 |
- Elevation at A = 85.38′
Elevation at B = 87.16′ - Elevation at A = 82.76′
Elevation at B = 82.87′ - Elevation at A = 80.42′
Elevation at B = 80.69′ - Elevation at A = 80.93′
Elevation at B = 80.77′ - Elevation at A = 81.39′
Elevation at B = 81.99′
Depth of drain at B below datum is 18′ – 0 1/8″
-
- 105′ 3″
- 116′ 77⁄16″
- 145′ 9¾”
- 174′ 411⁄16″
- 186′ 11½”
-
- 0.68′
- 0.92′
- 1.29′
- 1.60′
- 1.73′
- 2%
- 0.96′
- 70 feet
- 1.30%
- 2.08%
- A backsight
- A foresight or intermediate sight
- A geodetic datum is an elevation above mean average sea level.
