Civil Engineering - Elements of Remote Sensing MCQs Part 1

1. Which one of the following statements is correct ?

A.
Snow albedo falls at all wave length with the increase of grain size

B.
The effect of grain size on reflection is maximum in the near-IR region

C.
The effect of grain size on reflection is low in the visible region of the spectrum

D.
All of these

 Answer Option D

2. The refractive index of the ocean water:

A.
increases with salinity

B.
increases with temperature

C.
decreases with salinity

D.
decreases with temperature

 Answer Option A

3. The arrangement of terrain features which provides attributes: the shape, size and texture of objects, is called :

A.
spectral variation

B.
spatial variation

C.
temporal variation

D.
None of these .

 Answer Option B

4. Electromagnetic radiation :

A.
produces a time varying magnetic field and vice versa

B.
once generated, remains self-propagat-ing.

C.
is capable to travel across space

D.
consists of magnetic and electric fields

E.
All of these

 Answer Option E

5. Pick up the important characteristic of a target which facilitates its identification from the following:

A.
spectral variation

B.
spatial variation

C.
temporal variation

D.
polarisation variation

E.
All of these

 Answer Option E

6. Which one of the following frequency regions is a part of sun's radiation?

A. Ultraviolet frequency region

B. Visible frequency region

C. Infrared frequency region

D. Radio frequency region

E. All of these

 Answer Option E

7. The instruments which provide electromagnetic radiation of specified wave length or a band of wave lengths to illuminate the earth surface, are called :

A. sensonrs

B. passive sensors

C. active sensors

D. None of these

 Answer Option C

8. Due to pertubation of the orbit, satellite orbit parameters are frequently updated on measurements carried out by its

A. six ground stations

B. five ground stations

C. four ground stations

D. three ground stations

 Answer Option B

9. Coherence of two electromagnetic waves takes place if their phase difference is :

A. constant in time

B. constant in space

C. constant in time and space

D. None of these

 Answer Option C

10. The part radiation due to scattered/diffused radiation entering the field of view of a remote sensor other than that from the required target,

A. reduces the contrast of the image and also its sharpness

B. increases the contrast of the image but reduces the sharpness

C. increases both the contrast and sharpness

D. reduces the contrast but increases the sharpness

 Answer Option A

11. Which one of the following residual biases involves the GPS accuracy ?

A. Satellite dependent baises due to uncertainty in the orbital parameters of the satellite.

B. Receiver-depandent biases due to clock stability with line

C. Signal propagation baises due to the sphere and troposphere propogation.

D. All the above

 Answer Option D

12. Pick up the correct definition from the following with response to GIS.

A. Common boundry between two areas of a locality is known as adjacency.

B. The area features which are wholly contained within another area feature, is known so containment.

C. The geometric property which describes the linkage between line features is defined as connectivity.

D. All of these.

 Answer Option D

13. Which one of the following errors is produced by platform characteristics of the sensor ?

A. altitude variation

B. altitude

C. orbit drift

D. All of these

 Answer Option D

14. The coherence length over which there is a strong relationship between amplitudes is;

A. directly proportional to the bandwidth

B. inversely proportional to the bandwidth

C. the square of the bandwidth

D. none of these

 Answer Option B

15. In the given figure the phase of

A. crest A is π/2

B. B crossing is π

C. trough C is 3 π/2

D. All of these

 Answer Option D

16. If 0 is the angle of scan measured from the nadir, the ground distance swept by the sensor IFOV is proportional to :

A. sin2θ

B. cos2θ

C. sec2θ

D. tan2θ

 Answer Option C

17. Which one of the following statements is correct regarding the GPS satellites ?

A. The nominal altitude is about 20, 200 km

B. The inclination of axis satellite is 55°

C. The satellite transmits two L band signals (L1 with 1575.42 MHz and L2 with 1276.6 MHz)

D. All of these

 Answer Option D

18. Pick up the correct statement from the following:

A. Indian space effort started in 1962 with the establishment of a rocket.

B. Development of space (DOS) was established by the Government of India in 1972

C. Indian Space Research Organisation (ISRO) is responsible for the space technology and its application to various activities.

D. All of these

 Answer Option D

19. Rayleigh's criteria for a rough surface is: (where letters carry their usual meanings).

A. h > λ/Δ cos θ

B. h = λ/8 cos θ

C. h > λ/8 cos θ

D. h < λ/8 cos θ

 Answer Option C

20. Pick up the correct statement from the following :

A. The distance between two successive crests or troughs of a wave, is called, the wave length

B. The wave length is measured in metres and a fraction of a metre

C. The wave length is generally denoted by λ

D. The length of the crest from the mid point, is called amplitude

E. All of these

 Answer Option E

21. The basic requirement of any sensor system, is :

A. radiometric resolution

B. spatial resolution

C. spectral resolution

D. temporal resolution

E. All of these

 Answer Option E

22. Which one of the following helps to identify the objects on the earth surface ?

A. atmospheric window

B. signature

C. radiometric error

D. None of these

 Answer Option B

23. The spectral region of the electromagnetic radiation which passes through the atmosphere without much attenuation is known as:

A. ozone hole

B. atmospheric window

C. ozone window

D. black hole

 Answer Option B

24. Which one of the following statements is correct?

A. During the day, earth reflects solar radiation

B. During the day earth reflects both solar radiation the emission from its surface

C. During the night, earth emits radiation from its surface

D. All of these

 Answer Option D

25. The remote sensing techniques applied for the earth's surface features, is generally confined to the following wave lengths :

A. 0.4 to 1.3, 1.5 to 1.8, 2.2 to 2.6 μm

B. 2.2 to 2.6, 3.0 to 3.6, 4.2 to 5.0 μm

C. 4.2 to 5.0, 7.0 to 15.0 μm and 1 cm to 30 cm

D. All of these

 Answer Option D

26. The value of energy quantum for radiation of any frequency is proportional to :

A. the frequency

B. the reciprocal of the energy

C. the square of the frequency

D. the square root of the frequency

 Answer Option A

27. The phase difference of the waves 1 and 2 at A in the given figure is :

A. π/4

B. π/2

C. π

D. 3π/2

 Answer Option B

28. A perfectly black body :

A. is a diffuse emitter

B. absorbs all the radiations of every wave lengths

C. emits power of every wave length

D. All the above

 Answer Option D

29. Pick up the correct statement from the following :

A. When the electric field oscillates in the direction of the electric vector, a plane polarised wave is formed.

B. When the electric vector is in the plane of incidence, vertical polarisation is formed.

C. When the electric vector is at right angles to the plane of incidence, horizontal polarization wave is formed.

D. The plane containing the incident ray and normal to the reflecting surface at the point of incidence is called the plane of incidence.

E. All of these

 Answer Option E

30. Pick up the correct statement from the following:

A. Phase of a wave is expressed as a fraction of a period with respect to a refrence

B. Phase is usually specified by angular measure with one period being 360°

C. The reference for finding the phase of a wave is taken from the previous passage through zero from the negative to the positive direction.

D. All of these

 Answer Option D

31. A and B are two towers of equal height diametrically opposite on either side of the nadir point, at 3 km and 5 km distances. Which one of the following statements is correct?

A. Height displacement of A will be less than that of B

B. Height displacement of B will be less than that of A

C. Height displacement of A and B is equal

D. Height displacement of A and B will be towards each other

 Answer Option A

32. Remote sensing techniques makes use of the properties of-----emitted, reflected or diffracted by the sensed objects:

A. electric waves

B. soundwaves

C. electromagnetic waves

D. wind waves

 Answer Option C

33. Which one of the following parameters is accurate for DGPS.

A. Positional accuracies ~ 1 - 2 m if rover is less than 1-2 km from the reference station

B. Positional accuracies ~ 2 - 5m if rover is less than 2-5 fm from the reference station

C. Positional accuracies ~ 5 - 10 m if rover is less than 5-10 km from reference station

D. Positional accuracies ~ 5 - 10 m if rover is less than 25 km

 Answer Option A

34. The most widely used antenna in GPS is

A. Parabolid antenna

B. Microstrip antenna

C. Horn antenna

D. Slotted antenna

 Answer Option B

35. Which one of the following statements regarding remote sensing is correct.

A. The interaction of the electromagnetic radiation with the target

B. The emission of electromagnetic radiation from the target

C. both (a) and (b)

D. Neither (a) nor (b)

 Answer Option C

36. "An Electromagnetic wave falls on to a boundary between two loss less homogeneous media with different refractive indices, a part of the wave is reflected back to the incident medium and the rest is transmitted on to the second media". This phenomenon is known as :

A. Fresnel reflection

B. Fresnel refraction

C. Snell's law

D. None of these

 Answer Option A

37. Which one of the following relationship between the wave length (λ), and frequency and the speed (C) of the electromagnetic wave is correct ?

A. C = v + λ

B.

C. C = vλ

D.

 Answer Option C

38. The various stages occuring in GPS system are described below :1. Generation of an output to the user2. Detection of the GPS signal3. Processing the data in the built-in-computer4. Decoding the GPS signal.The correct sequence of the stages is :

A. 1, 2, 3, 4

B. 2, 3, 4, 1

C. 2, 4, 3, 1

D. 3, 1, 2 , 4

 Answer Option C

39. The reflection of solar energy is characterised by the water content in the leaf, in the reflective optical infrared:

A. visible (0.4 - 0.7 μm) region

B. near-IR (0.7 - 1.3 μm) region

C. short wave-IR (1.3 - 2.7 μm) region

D. None of these

 Answer Option C

40. Which one the following is a correct statement?

A. The vertical section of the soil extending into the parent material, is called profile

B. The layers of the soil parallel to the earth surface, are called horizons.

C. The transitional layer between two adjoining horizons, is called boundary.

D. All of these

 Answer Option D

41. The entire range of the electromagnetic spectrum spans a large spectrum of wave lengths varying from:

A. 10-10 to 106 m

B. 10-8 to 106 m

C. 10-10 to 1010 m

D. 10-8 to 108 m

 Answer Option A

42. Pick up the correct statement from the following :

A. Topology describes the geometric characteristic of objects which do not change under transformations and are independent of any coordinate system

B. Topological characteristics of an object are independent of scale measurement

C. The three elements of topology are adjacency, containment, and connectivity

D. All of these

 Answer Option D

43. Which one of the following parameters is considered to determine the reflectance of a vegetation canopy

A. Solar zenith angle

B. Azimuth angle

C. Look angle

D. Number and arrangement of leaves

E. All of these

 Answer Option E

44. A reduction of nitrogen nutrient in plants :

A. affects leaf colour

B. reduces pigment concentration

C. increase the visible reflectivity

D. All of these

 Answer Option D

45. Pick up the correct statement from the following:

A. The surface defined by the locus of points having same phase, is called a wave front.

B. The wave whose surface of constant phase are parallel planes, is known as a plane wave.

C. The relative phase difference between the waves is important and not the absolute phase of a point on the wave

D. All of these

 Answer Option D

46. Leaf reflactance depends primarily on :

A. the pigments

B. internal cell structure

C. equivalent water content

D. All of these

 Answer Option D

47. Pick up the correct statement from the following

A. The ratio of the up flux and down flux just above the snow surface, is called albedo

B. Spectral albedo of snow is calculated for the semi-infinite snow thickness

C. Water equivalent height of snow is the height of water column obtained by melting snow.

D. A homogeneous snow pack is one whose average grain size does not vary with depth.

E. All of these

 Answer Option E

48. Pick up the correct statement from the following:

A. Permeability is a measure of conducting the magnetic lines of force in the material.

B. Permeability is a measure of the extent to which magnetic lines of force can penetrate a medium.

C. Permeability is expressed as the ratio of the magnetic flux density (B) to the field strength of the magnetizing field.

D. The force between the magnetic poles is inversely proportional to the permeability of the medium.

E. All of these

 Answer Option E

49. Pick up the correct statement from the following:

A. In remote sensing technique, the observation place, is called a platform

B. Platforms may be either stationary or mobile

C. Spatial resolution of the imaging system becomes poorer with increase of platform height.

D. Area coverage of the imaging system increases with the increase of the platform altitude.

E. All of these

 Answer Option E