List of top Geomatics Engineering Questions asked in GATE Geomatics Engineering

A 23 cm square format camera with a focal length of 152.4 mm is used for taking vertical aerial photographs with 60% end-lap. These photographs are viewed under a stereoscope with a base-height ratio of 0.15. The vertical exaggeration while stereoviewing these photographs is ___________ (Answer in integer).

In a map based on the UTM projection, the grid distance is in error with respect to the geodetic distance by about one in four thousand. If the map distance is 3 cm and the map scale is 1:25,000, then the geodetic distance is ___________m (rounded off to 2 decimal places).

Consider an infinitely sized square grid pattern (as shown in the figure below) overlaid on a flat ground at an elevation of 120 m above mean sea level. An image is taken by a camera from flying height of 450 m above mean sea level. Assume that the flying height remains constant throughout the operation of the flight. The flying direction is along the line FL, as shown in the figure below. The camera is looking in the off-nadir in the flight direction resulting in a low oblique photograph. Which of the following statements for the resulting low oblique photograph is/are correct? 

Consider a pair of overlapping vertical aerial photographs taken from a flying height of 665 m above a point A on the ground, with a camera having a focal length of 152.4 mm. The height of the point A above the mean sea level is 535 m. The parallax bar reading of the point A as measured from the photographs is 10.96 mm. Assuming the air base to be 400 m, the parallax bar constant is _________ mm.

Select the correct statement in the context of relief displacement in vertical aerial photographs.
Which one of the following parameters does NOT affect the scale of a vertical aerial photograph?

In a Survey of India topographic map of scale 1:50,000, the contours are drawn conventionally at intervals of __________ m.

Which one of the following map projections is NOT conformal?
In a Geographic Information System database, a stream is represented by a line and houses are represented by polygons. The pollution in the stream is affecting houses within a distance of 500 m on both sides. Which vector data analysis operations should be performed to identify houses affected by the pollution in the stream?
Which one of the following statements is NOT correct in the context of shapefile?
The value of the convolution of $f(x) = 3 \cos 2x$ and $g(x) = \frac{1}{3} \sin 2x$ where $x \in [0, 2\pi]$, at $x = \frac{\pi}{3}$ is ............................. (Rounded off to 2 decimal places).
The zone number of Universal Transverse Mercator (UTM) projection having a longitude of $67^\circ 20' 30''\text{E}$ is \underline{\hspace{1.2cm}} (In integer).

The table provides the X- and Y-coordinates of the points, measured in row and column of a raster with a cell size of 1 meter, and their known values. Using inverse distance weighted (IDW) interpolation method and Euclidean distance, the interpolated value at Point 0 is ................. (Rounded to 2 decimal places). A constant rate of change in value between points should be assumed. 

 

Point$X$$Y$Value
1697627
2596710
3747913
06967?

 

The relative radiance value of a facet of a Triangulated Irregular Network (TIN) can be computed using: \[ R_f=\cos(A_f-A_s)\sin(H_f)\cos(H_s)+\cos(H_f)\sin(H_s) \] Where, $R_f$ is the relative radiance value of a facet, $A_f$ is the facet’s aspect, $A_s$ is the sun’s azimuth angle, $H_f$ is the facet’s slope and $H_s$ is the sun’s altitude. Suppose a facet of a TIN has a slope value of $10^\circ$ and an aspect value of $297^\circ$ and sun’s azimuth of $315^\circ$. For sun’s altitude angle of $65^\circ$, the relative radiance value of this facet is ................. (Rounded off to 2 decimal places).
The range accuracy with a microsecond accurate clock in the GNSS receiver is about 300 m. If we improve the clock accuracy to $3.33 \times 10^{-x}$ s, the range accuracy becomes 1 cm. The value of $x$ is ............ (In integer).
Assume the speed of light to be $c = 3 \times 10^8$ m/s and that no other errors are being considered.
Hint: error-free range = speed of light $\times$ time of travel of the signal

In the network shown below, after converting it to a topological graph, which of the following statement(s) is/are TRUE? (Assume there are no pseudo-nodes) 

For the following data, the slope $(m)$ and intercept $(c)$ of the least squares fitted straight line $(Y=mX+c)$ are given as:

The figure shows three distance observations $D_1$, $D_2$ and $D_3$. The table lists values of these observations and the corresponding weights. Assuming uncorrelated observations, the most probable values by the least squares approach for these measurements are ............................. (Rounded off to 3 decimal places). \[ \begin{array}{|c|c|c|} \hline \text{Distance} & \text{Measurement (m)} & \text{Weight} \\ \hline D_1 & 40.150 & 1 \\ \hline D_2 & 40.180 & 2 \\ \hline D_3 & 80.390 & 1 \\ \hline \end{array} \]

Match the following errors (Column 1) in spatial data digitization with their descriptions (Column 2).
 

Column 1Column 2
(P) Mis-located entities2) Points, lines or boundary segments digitized in wrong place
(Q) Missing labels4) Undefined polygons
(R) Artefacts of digitization3) Undershoots, overshoots, wrongly placed nodes, loops or spikes
(S) Duplicate labels5) Two or more identification labels for same polygon
(T) Duplicate entities1) Points, lines or boundary segments digitized twice
A sensor converts the influx of light linearly to digital code through voltage changes. The sensor has a voltage range of 0-5 V and the maximum number of codes that it can quantize the voltage change is 2048. The bit-size of the quantizer is ............................. (In integers).
The minimum number of 2-dimensional ground control points (GCPs) required for second-order polynomial mapping for image georeferencing is:
A child travelling in a bus is staring at the wheels of a car. To the child’s amusement the car wheels appear to spin backwards, but the car moves forward. This perception is because of the nature of our human visual sensory system, and is attributed to ..................
To store a 3 band, 4-bit, $512\times512$ size image (without header) the number of storage bits required are ..................
Which of the following statement(s) is/are CORRECT?
Which of the following statement(s) is/are CORRECT?