Geodesy Board Practice Exam

These questions are part of the practice quiz. Start practicing

• Grid azimuth is the same as geodetic azimuth only when the point of observation falls on the _______ meridian.
• ______ in a geodetic leveling instrument exists when the plane of the image and the plane of the cross-hairs do NOT coincide, and should be eliminated by _____ the objective, eyepiece, or both.
• Which of the following statements is a property of the Mean Sun?
• Using the least squares method, determine the correction, in millimeters, to the field difference in elevation along route 2.
• Which statement about the radii of curvature on a reference ellipsoid is true?
• Which statement best describes a priori observation weights?
• Using the weighted value method, what is the most probable difference in elevation between BM 12 and BM 13?
• GNSS observation time depends on which factors?
• When LAT equals LMT, which is true?
• Which statement correctly describes GPS time relative to UTC?
• How many longitudinal zones does the UTM system divide the globe into?
• What is the primary goal of precise geodetic leveling, and what uncertainty is typically achieved?
• What is the adjusted value of angle D in the least-squares adjustment of the angles?
• A method of establishing a geodetic control surveys consisting of connected triangles or polygons where all _____ are measured is called _____
• Which statement about geographic to grid conversion is NOT true?
• What is the role of cycle-slip detection in GNSS network processing?
• ______ gravity anomaly refers to small regional variations in the Earth's gravity field resulting from density variations in underlying rocks.
• In geographic coordinate systems, what is the central meridian?
• Which term describes the height above the geoid measured along the local vertical?
• The azimuth measured in map grid coordinates is known as which type of azimuth?
• Which of the following is not a type of radiometric correction used in image processing when there is interference with the radiance measured by an instrument?
• Which two times define the equation of time?
• How does satellite elevation influence the severity of tropospheric delay?
• What is the rate of change in longitude per year, in centimeters, for ZGN-6 between 1990 and 2010?
• Which statement about the Mean Sun is accurate?
• In ellipse geometry, the first eccentricity e is defined as e = sqrt(1 - (b^2 / a^2)). Which option correctly shows this relation?
• What are grid coordinates in a map projection?
• Which pair of time scales are involved in the equation of time?
• Which formula expresses orthometric height H in terms of ellipsoidal height h and geoid undulation N?
• Ephemeris data describe satellite positions as a function of time.
• Distinguish between an ellipsoid and the geoid.
• Which database model stores data in a tree-like structure with parent records linked to a root?
• What is the primary purpose of generalization in map making?
• The equation of time equals which difference of times?
• The ratio 1/133000 in the distance accuracy example represents which type of accuracy?
• The LMB through the ____________ shall calibrate and register UAS used for land surveying pursuant to Section 22, DAO No. 2007-29.
• In the expression ±(0.2 mm + 5 ppm), the 5 ppm term is distance-dependent.
• For observers on the equator, which statement is true?
• Using the three routes, what is the adjusted difference in elevation between BM 34 and BM 35, in meters?
• Which statement about the lengths of solar and sidereal years is true?
• What is the purpose of including constraint equations in a least squares adjustment?
• What is the total shift of the station coordinates from date of establishment up to re-observation, in meters? Assume 1" equals 30 meters.
• Distinguish geodetic coordinates from grid coordinates.
• What is the primary purpose of a geodetic datum?
• In the meridian radius of curvature formula, the denominator is raised to which exponent?
• What is variance component estimation (VCE) used for in least squares adjustment?
• What is the published azimuth of the line AJ10-AJ24?
• What is the semi-major radius of Clarke's ellipsoid of 1866 in meters?
• In a GNSS network, what does the baseline represent?
• Which of the following equations is/are incorrect for the given grid conversion formulas?
• Geoid undulation N is defined as the height of the geoid above the ellipsoid.
• Identify the pair of projections and their typical applications.
• The equation of time relates Local Apparent Time to Local Mean Time by which quantity?
• When geoid and ellipsoid coincide at a datum origin, the deflection and the ______ and the separation between the ellipsoid and geoid become ______ at the origin.
• Least squares is a method of adjusting observations in which the sum of the squares of which quantity is minimized?
• The radius of curvature of the prime vertical N is equal to which expression?
• In height conversion, ellipsoidal height h equals orthometric height H plus geoid undulation N.
• What do the seven Helmert parameters represent in a coordinate transformation?
• What is the purpose of the zone-based false origin in UTM?
• As the Sun moves counterclockwise relative to the fixed stars, which coordinate is continuously increasing?
• How would you differentiate a coordinate reference system from a map projection?
• In GNSS, which components make up PNT?
• What is ellipsoidal height h in relation to the reference ellipsoid?
• An image with 11-bit radiometric resolution can contain pixel values within the range _________.
• In the celestial sphere, which term refers to the point directly beneath the observer?
• The GPS-derived height of a control point is 56.439 meters, while the orthometric elevation of the same point is 8.795 meters. Determine the separation between the ellipsoid and the geoid at the location of the control point.
• Authalic map projections such as the Sinusoidal projection and the Gall-Peters projection show the correct sizes of countries relative to each other but distort _________.
• The correct formula to solve the coefficient p for geographic to grid conversion is:
• In leveling, a point is defined as the location where a backsight on a leveling rod is taken from one instrument station and a foresight is taken to the next instrument station. Which term describes that point?
• When constructing an ellipse, the length of the string is
• Which instrument component is used to provide a stable base for positioning a surveying instrument on site?
• What is the name of the great circle that passes through the nadir and the south celestial pole?
• The distance from the origin to one of the ellipse's focus is
• For a UAS lot survey, the hard copy of the ortho-image covering the entire project must be printed not exceeding 54x54 cm.
• Which statement correctly differentiates vertical datum from a height system?
• There is a need for the ____ correction in transforming geodetic to grid azimuths because the geodetic line is a curved line when projected onto a plane.
• What is a 7-parameter Helmert transformation used for in datum shifts?
• Which statement about the Mean Sun's motion regarding right ascension is correct?
• Define precise point positioning (PPP) in GNSS.
• Which height is commonly obtained from GPS measurements?
• What are NAD27 and NAD83, and how do they differ?
• In carrier-phase GNSS observations, what is a cycle slip?
• For an 11-bit radiometric image, what is the maximum pixel value?
• Which term denotes the great circle that passes through the nadir and the south celestial pole?
• In least squares adjustment, what is the impact of adding constraint equations?
• What is carrier-phase ambiguity, and why is its resolution important?
• What is UTM in geodesy?
• Grid length differs from geodetic length by the amount of a correction based on the ______ for the given line.
• The angle in the plane of projection between a straight line and the central meridian of a rectangular coordinate system is Called _______ azimuth.
• Which statement best describes the primary advantage of precise point positioning (PPP) in GNSS processing?
• Which observation type provides centimeter- to millimeter-level precision only after resolving integer ambiguities?
• Grid azimuth equals geodetic azimuth when the observation lies on the central meridian.
• What is differential GNSS (DGPS) and its typical accuracy improvement?
• Which statement best describes a 7-parameter Helmert transformation in datum shifts?
• Height is the distance measured along a _____ between a point on the earth's surface and a reference surface.
• Which of the following is defined as the first eccentricity of an ellipse?
• List common error sources in leveling surveys.
• GNSS____ resolution may be accomplished by interchanging the antenna and receiver assemblies between two stations.
• How does a coordinate system orientation influence a transformation?
• The relationship between geocentric latitude ψ and reduced latitude β is which of the following?
• If Local Apparent Time equals Local Mean Time, the equation of time is:
• What is the purpose of ambiguity resolution in RTK?
• The sum of the squared residuals of four measurements of a geodetic baseline is 0.0188. What is the probable error of the baseline?
• Which statement is true about the Mean Sun according to the material?
• Geoid undulation, N, represents the separation between the ellipsoid and the geoid.
• Why are a priori observation weights used in adjustment of GNSS data?
• If BM 12 has an elevation of 27.048 meters and is higher than BM 13, what is the most probable elevation of BM 13?
• Name the two main GNSS observation types and summarize their characteristics.
• GNSS multipath refers to what phenomenon, and why does it matter for accuracy?
• In the horizon coordinate system, which two quantities define the position of a celestial object?
• What is the acceptable minimum accuracy in image classification?
• Which condition is part of the Gauss-Markov assumptions ensuring the least squares estimator is BLUE?
• Atmospheric refraction tends to diminish the effect of earth curvature by approximately _______ per cent.
• In GNSS, ephemeris data describe satellite positions as a function of which variable?
• In the equation h = H + N, what does N stand for?
• At the datum origin where geoid and ellipsoid coincide, the vertical separation between the two surfaces is what value?
• In a post-adjustment network, what does the standard deviation of a coordinate correspond to?
• Geodetic azimuth in the Philippines is reckoned from which direction?
• What does the Gauss-Markov theorem tell us about least squares estimators?
• What is the purpose of robust or outlier-tolerant least squares?
• The zero-point for ______ is the vernal equinox.
• In which projection are great circles represented as straight lines in all aspects?
• In least-squares adjustment, the quantity whose squares are minimized is the residuals.
• The correct formula to solve the coefficient q for grid to geographic conversion is:
• The relationship between geodetic latitude Φ and reduced latitude β is which of the following?
• The relationship between geocentric latitude ψ and geodetic latitude Φ is which of the following?
• Which statement about meridian convergence corrections in survey practice is NOT true?
• Orthometric height is defined as height above which surface?
• Name common geodetic datums used in the United States for mapping and positioning.
• In a least-squares adjustment of three measured horizontal angles, what is the adjusted value of angle A?
• In the same angle adjustment, what is the adjusted value of angle C?
• Inverse flattening is defined as the reciprocal of what quantity?
• How does the covariance matrix describe a post-adjustment network's uncertainty?
• In spherical geometry, the sum of the three interior angles of a spherical triangle is greater than 180 degrees by the spherical excess. This statement describes which relation?
• Which technique involves transmitting a signal from a ground station, reflecting off retro-reflectors on satellites, and receiving back at the station?
• Which surface is defined as mean sea level extended through the continents and used as a reference for orthometric heights?
• Root mean square expresses the ______ of point measurements.
• What are false easting and false northing in map projections?
• What is WGS84, and where is it used?
• At the equator, which radius is equal to the semi-major axis length?
• The radius of curvature of the ellipsoid varies with latitude and the shortest lies at the ______.
• Which statement correctly describes the typical magnitude of the coefficients p and q in grid conversions?
• Which statement describes a geocentric datum?
• What mathematical contrivance is used to characterize local distortions due to map projection?
• What is a GNSS baseline?
• The GNSS measured distance is called a pseudo-range because it has a constant bias error due to the clock error of the ______.
• In which theorem are the angles A, B, and C of a spherical triangle equal to the corresponding angles of a plane triangle whose sides are a, b, and c, each increased by one-third the spherical excess of the triangles?
• If ellipsoidal height is 50 m and geoid undulation is 5 m, what is the orthometric height?
• Which statement about the World Polyconic Grid is true?
• What is the rate of change in latitude per year, in centimeters, for the PRS92 station ZGN-6 between 1990 and 2010?
• Why is error propagation important when transforming coordinates between datums or projections?
• A least squares equation expressing that the three measured angles of a triangle must equal 180 degrees plus the spherical excess of the triangle is known as which type of equation?
• Leveling-based datums versus gravimetric datums: which statement is correct?
• In a conventional GNSS RTK survey, the data transfer from the base to the rover can be made either through a ______ or a telephone link.
• What is the term for the setting that stops GNSS receivers from using satellites near the horizon?
• How are covariance and correlation used in evaluating geodetic measurements?
• In classical triangulation, the procedure for first-order accuracy positioning requires how many directions?
• What does the geoid represent within geodesy?
• What does a nonzero covariance between coordinates indicate in a network adjustment?
• Which datum is commonly used with State Plane Coordinate Systems in the United States?
• The spectral region of the electromagnetic radiation which passes through the atmosphere without much attenuation is known as:
• The free-air gravity anomaly height correction for every meter above sea level is ______ mgal.
• Which of the following best describes the geoid?
• Free-air anomaly is the difference between the _____ gravity and theoretical gravity at a point.
• Which statement best describes the difference between RTK and standard DGPS in terms of corrections and ambiguity resolution?
• What is the name of the angle between the horizon and the polar axis?
• Which process reduces the number of points in a polyline while preserving its overall shape?
• What is the tropospheric delay, and how does elevation affect it?
• Which term describes a star that never sets for a given latitude due to proximity to a celestial pole?
• If the traverse had 12 occupied stations, what is the order of the traverse accuracy level?
• What differentiates a geocentric datum from a local datum?
• What term describes the spectral region that experiences minimal atmospheric attenuation?
• Which statement describes the Mean Sun's right ascension behavior?
• Unlike conventional real-time kinematic surveys which use a single base station, real-time network RTK GPS surveys use several base stations mounted where?
• An example of the measurement accuracy notation used for a baseline observation is which of the following?
• A 2.5-km baseline is measured with an electronic total station. If the vendor's accuracy specification of the instrument is ± (5mm + 2ppm).calculate the accuracy of the measured distance to the nearest thousand.
• In image classification, which method yields higher accuracy when the classes in the image match on-ground land-use patterns?
• In GNSS surveying, the essential direct measurement must be with the satellites rather than the stations in the project network; this is described as line of sight to satellites and control.
• The Mean Sun property: What path does it move along?
• If the azimuth error of closure for the traverse is required in seconds, what is the error?
• In route planning, what analysis determines the path of least impedance between two points considering topography and travel restrictions?
• Which of the following statements are true? A) 365.25 solar days in a year. B) 366.25 sidereal days in a year. C) 364.25 sidereal days in a year. D) Both A and B.
• In the celestial sphere, which term refers to the point directly below the observer?
• The compression of a circle along a diameter to form an ellipse or ellipsoid of revolution is described by which term?
• Which parameter is used to correct the difference between grid length and geodetic length along a line?
• Differentiate GPS time, International Atomic Time (TAI), Coordinated Universal Time (UTC), and Terrestrial Time (TT).
• The equation of time is the difference between which two times?
• A 200-meter baseline distance is measured with an electronic total station. If the vendor's accuracy specification of the instrument is ±(5mm + 2ppm), the precision of the measured distance relative to the baseline is closest to which value?
• What is the map called where geographic areas are distorted in proportion to an attribute such as population?
• Which equation correctly relates reduced latitude β to geodetic latitude Φ?
• The free-air anomaly is defined as the difference between observed gravity and which gravity value at a point?
• What is ITRF, and why is it important for global geodesy?
• In real-time network RTK GPS surveys, network corrections are provided by several permanently operating reference stations.
• Which of the following combinations will NOT define an ellipse?
• Define ellipsoidal height and orthometric height, and give their relationship.
• What is geoid undulation N, and how is it used in height conversion?
• Which term describes the bearing measured from north in the reverse direction of a line, as used in grid length corrections?
• The _____ maintains the geodetic control network of the Philippines.
• In a set of repeated measurements, the root mean square mainly reflects the measurement's ______.
• Using the least squares method, determine the correction, in millimeters, to the field difference in elevation along route 1.
• What is the primary purpose of conducting a network adjustment in surveying?
• In Philippine geodesy, the Vigan Datum is best described as which of the following?
• An authalic radius is the radius of a hypothetical perfect sphere which has the same surface ______ as the reference _______.
• A 2-km baseline is measured with an electronic total station. If the instrument accuracy is 5 mm + 5 ppm, what is the accuracy of the measured distance to the nearest thousandth?
• Which term describes a map that emphasizes a single data theme such as population, often using color or symbols?
• Very long-range interferometry involves the simultaneous measurement of the times of signals from very distant astronomical objects such as ______.
• When the geoid coincides with the ellipsoid at the datum origin, the normal to the ellipsoid is aligned with which line at the datum origin?
• In both geocentric and geodetic coordinate systems, the geodetic longitude λ is equal to which expression?
• Why is weighting important in least squares adjustments, and what does weight represent?
• Which set of factors does NOT influence GNSS observation time?
• What is the purpose of datum transformations in practice?
• Under DAO 2007-29, which division shall calibrate and register UAS used for land surveying?
• Which radiometric correction option is not a standard correction used to adjust radiance due to atmospheric conditions?
• Redundancy in a geodetic network refers to what?
• In the published accuracy statement of an electronic total station, the value 0.2 mm in ±(0.2 mm + 5 ppm) refers to which type of constant?
• Which measurement is the primary focus in trilateration surveys?
• In GNSS, a pseudo-range measurement is biased by clock error of which component?
• Describe the local tangent plane concept and when it is appropriate to use it.
• The angle between the equatorial plane and a line joining a point on the ellipsoid to the center of the ellipsoid is called ____ latitude.
• The equation of time expresses the difference between LAT and LMT.
• What is the ionospheric delay, and how is it mitigated in GNSS?
• In least squares adjustment, which statement best describes a residual?
• Define a closed traverse and how misclosures are assessed.
• If ellipsoidal height h equals 100 meters and geoid height N equals 30 meters, what is the orthometric height H?
• The radius of curvature in the meridian M is equal to which expression?
• Which instrument's accuracy specification is given as 5 mm + 5 ppm in the distance example?
• Which grid system was the first used in the Philippines and predecessor of UTM?
• Global navigation satellite systems enable receivers to determine their location using time signals transmitted along a line of sight by radio from satellites.
• A star that never sets below the horizon for a given latitude due to near-pole position is called what?
• In the equation h = H + N, what does H stand for?
• In GNSS surveying, the direct _____ has to be with the satellites and not with the stations in the project ______network.
• The forward and back azimuths of a geodetic line do not differ by exactly 180 degrees due to the _____.
• A geodetic traverse starts at a point with a given position and with a known ______ to another point and then ______ are measured between a series of survey points.
• Which of the following values is most commonly used as the inverse flattening?
• Which data condition makes robust least squares most beneficial?
• In the horizon coordinate system, which pair of values defines the position of a celestial object?
• In a weighted-value adjustment of four survey routes, Route 1 is assigned a weight value of 1. What is the summation of the weights for all four routes?