Element of Remote Sensing - Multiple Choice Questions

Element of Remote Sensing Multiple Choice Questions

 1. compression force in two end posts The pin of a rocker bearing in a bridge is designed for_________________?. 

A. bearing and shear

B. bending and shear

C. bearing and bending

D. bearing, shear and bending. 

Answer = bearing, shear and bending


2. The portal bracing in a truss bridge is used to_____________________?. 

A. transfer load from top of end posts to bearings

B. keep the rectangular shape of the bridge cross-section

C. stiffen the structure laterally

D. prevent the sidesway buckling of top chord. 

Answer = transfer load from top of end posts to bearings


3. The centrifugal force due to curvature of track is assumed to act on the bridge at a height of___________________?. 

A. 1.23 m above the rail level

B. 1.50 m above the rail level

C. 1.83 m above the rail level

D. 2.13 m above the rail level. 

Answer = 1.83 m above the rail level


4. If the loaded length of span in meters of a railway steel bridge carrying a single track is 6 m, then impact factor is taken as_________________?. 

A. 0

B. 0.5

C. between 0.5 and 1.0

D. 1.0. 

Answer = between 0.5 and 1.0


5. The diameter of base of conical flare of a steel stack is_____________________?. 

A. less than d

B. equal to d

C. more than d

D. any of the above. 

Answer = more than d


6. The capacity of the smallest pressed steel tank is__________________?. 

A. 1000 litre

B. 1650 litre

C. 1950 litre

D. 2450 litre. 

Answer = 1950 litre


7. Steel tanks are mainly designed for_______________________?. 

A. weight of tank

B. wind pressure

C. water pressure

D. earthquake forces. 

Answer = water pressure


8. Minimum pitch provided in riveted steel tanks is________________?. 

A. 1.5 d

B. 2.0 d

C. 2.5 d

D. 3.0 d. 

Answer = 3.0 d


9. As per IS : 875, for the purposes of specifying basic wind velocity, the country has been divided into_____________________?. 

A. 4 zones

B. 5 zones

C. 6 zones

D. 7 zones. 

Answer = 6 zones


10. The external wind pressure acting on a roof depends on__________________?. 

A. degree of permeability of roof

B. slope of roof

C. both (A) and (B)

D. none of the above. 

Answer = slope of roof


11. The basic wind speed is specified at a height 'h' above mean ground level in an open terrain. The value of'h' is__________________?. 

A. 10 m

B. 20 m

C. 25 m

D. 50 m. 

Answer = 10 m


12. The live load for a sloping roof with slope 15°, where access is not provided to roof, is taken as_______________?. 

A. 0.65 kN/m2

B. 0.75 kN/m2

C. 1.35 kN/m2

D. 1.50 kN/m2. 

Answer = 0.65 kN/m2


13. For the buildings having a low permeability, the internal wind pressure acting normal to the wall and roof surfaces is taken as__________________?. 

A. zero

B. ±0.2p

C. ± 0.5 p

D. ±0.7p where p is basic wind pressure. 

Answer = ±0.2p


14. To minimize the total cost of a roof truss, the ratio of the cost of truss to the cost of purlins shall be_______________?. 

A. 1

B. 2

C. 3

D. 4. 

Answer = 2


15. The minimum thickness of plates in a steel stack should be___________________?. 

A. 4 mm

B. 5 mm

C. 6 mm

D. 8 mm. 

Answer = 6 mm


16. The maximum permissible span of asbestos cement sheets is______________________?. 

A. 650 mm

B. 810 mm

C. 1250 mm

D. 1680 mm. 

Answer = 1680 mm


17. The maximum spacing of vertical stiffeners is_________________?. 

A. 1.33 d

B. 1.25 d

C. 1.5 d

D. 1.75 d. 

Answer = 1.5 d


18. The forces acting on the web splice of a plate girder are__________________?. 

A. axial forces

B. shear and axial forces

C. shear and bending forces

D. axial and bending forces. 

Answer = shear and bending forces


19. Minimum spacing of vertical stiffeners is limited to________________?. 

A. d/4

B. d/3

C. d/2

D. 2d/3. 

Answer = d/3


20. Intermediate vertical stiffeners in a plate girder need be provided if the depth of web exceeds___________________?. 

A. 501

B. 851

C. 200 t

D. 2501. 

Answer = 851


21. The web crippling due to excessive bearing stress can be avoided by_________________?. 

A. increasing the web thickness

B. providing suitable stiffeners

C. increasing the length of the bearing plates

D. none of the above. 

Answer = increasing the length of the bearing plates


22. Horizontal stiffener in a plate girder is provided to safeguard against_______________?. 

A. shear buckling of web plate

B. compression buckling of web plate

C. yielding

D. all of the above. 

Answer = compression buckling of web plate


23. Economical depth of a plate girder corresponds to_________________?. 

A. minimum weight

B. minimum depth

C. maximum weight

D. minimum thickness of web. 

Answer = minimum weight


24. The overlap of batten plates with the main members in welded connections should be more than____________________?. 

A. 3t

B. 4t

C. 6t

D. 8t where t = thickness of the batten plate. 

Answer = 4t


25. Lacing bars in a steel column should be designed to resist_________________?. 

A. bending moment due to 2.5% of the column load

B. shear force due to 2.5% of the column load

C. 2.5% of the column load

D. both (A) and (B). 

Answer = shear force due to 2.5% of the column load


26. If the 20 mm rivets are used in lacing bars, then the minimum width of lacing bar should be______________?. 

A. 40mm

B. 60mm

C. 80mm

D. 100mm. 

Answer = 60mm


27. Formation of snow occurs if the cloud temperature is________________?. 

A. Just above the freezing point

B. At the freezing point

C. Below the freezing point

D. None of these. 

Answer = Below the freezing point


28. 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 = All of these


29. 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 = All of these 


30. Which one of the following statement is incorrect regarding the electromagnetic radiation ?. 

A. These are produced by the motion of electric charge

B. The oscillation of charged particles sets up changing electric fields

C. The changing electric fields induce the changing magnetic fields in the surrounding medium

D. None of these. 

Answer = None of these


31. The ratio of the total solar radiant energy returned by a planetary body to the total radiant energy incident on the body, the called________________?. 

A. Reflectance

B. Reflectance factor

C. Albedo

D. None of these. 

Answer = Albedo


32. 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 = Signature


33. The changes in the reflectivity/emissivity with time, is called ?. 

A. Spectral variation

B. Spatial variation

C. Temporal variation

D. None of these. 

Answer = Temporal variation


34. Due to perturbation 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 = Five ground stations


35. The reflection of solar energy is characterised by the water content in the leaf, in the reflective optical infrared______________?. 

A. Visible (0.4 –

B. Near-IR (0.7 –

C. Short wave-IR (1.3 –

D. None of these. 

Answer = Short wave-IR (1.3 –


36. For interpolation of satellite data used for monitoring dynamic changes that occurs on the earth surface, the most suitable orbit for the satellite is______________?. 

A. Circular orbit

B. Sun-synchronous orbit

C. Near polar orbit

D. None of these. 

Answer = Sun-synchronous orbit


37. Which one of the following quantities forms the basis of radiometry ?. 

A. Radiant energy (Q)

B. Radiant flux (╬Že )

C. Radiant intensity (I)

D. All of these. 

Answer = All of these


38. Electromagnetic spectrum contains________________?. 

A. Gamma rays (wave length < 10-10 m)

B. Ultraviolet rays (wave length < 10-6 m)

C. Infrared rays (wave length < 10 -4 m)

D. All of these. 

Answer = All of these


39. Pick up the correct definition from the following with response to GIS_______________?. 

A. Common boundary 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 = All of these


40. The normal altitude of GPS satellite is about________________?. 

A. 16,200 km

B. 20,200 km

C. 24,400 km

D. 36,100 km. 

Answer = 20,200 km


41. The code based GPS receivers are generally used for_________________?. 

A. Vehicle tracking

B. Land navigation

C. Trans movement

D. All of these. 

Answer = All of these


42. Geodimeter is based on_________________?. 

A. Propagation of modulated light waves

B. Propagation of infrared radiation

C. The visible light as carrier with frequency of the order of 5 × 1014 Hz

D. High frequency radio waves. 

Answer = Propagation of modulated light waves


43. Pick up the correct statement from the following ?. 

A. The refractive index of a medium varies according to the wavelength of the radiation,

B. The variation of the refractive index with wave length, is called dispersion,

C. The splitting of colours of white light by passing through a prism is caused due to dispersion

D. All of these. 

Answer = All of these


44. 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 = Spatial variation


45. 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. All of these. 

Answer = All of these


46. If flying height of a spacecraft is H, the length of air base is B and the parallax difference between two points is dp, then the difference in height___________________?. 

A. h = dp/(B/H)

B. h = (B/H) dp

C. h = dp/(H/B)

D. h = (H/B) dp. 

Answer = h = dp/(B/H)


47. 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 = All of these


48. Leaf reflectance depends primarily on______________?. 

A. The pigments

B. Internal cell structur

C. Equivalent water content

D. All of these. 

Answer = All of these


49. Critical angle of electromagnetic radiation takes place if__________________?. 

A. Angle of incidence is equal to angle of refraction

B. Angle of incidence is greater than the angle of refraction

C. Angle of incidence is equal to 90°

D. Angle of refraction is equal to 90°. 

Answer = Angle of refraction is equal to 90°


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

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

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

C. Signal propagation biases due to the sphere and troposphere propagation

D. All the above. 

Answer = All the above


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


52. Electromagnetic radiation_______________?. 

A. Produces a time varying magnetic field and vice versa

B. Once generated, remains self-propagating

C. Is capable to travel across space

D. All of these. 

Answer = All of these


53. DGPS is based on the concept that bias errors in the position of locations in a given local area, are same if their distances are within___________________?. 

A. 25 km

B. 50 km

C. 75 km

D. 100 km. 

Answer = 100 km


54. Earth observations from a satellite platform provide____________?. 

A. Synoptic view of a large area

B. Constant solar zenith angles and similar illumination conditions

C. Repetitive observations of the same area with intervals of a few minutes to a few weeks

D. All of these. 

Answer = All of these


55. 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. All of these. 

Answer = All of these


56. The GPS space segment consists of Navigation Satellite Timing and Ranging whose number is_______________?. 

A. 8

B. 12

C. 16

D. 24. 

Answer = 24


57. 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 = The frequency


58. Which one of the following geometric errors of satellite sensors is random ?. 

A. Scan skew

B. Panoramic distortion

C. Earth rotation

D. Altitude variation. 

Answer = Altitude variation


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

A. Ultraviolet frequency region

B. Infrared frequency region

C. Radio frequency region

D. All of these. 

Answer = All of these

Previous Post Next Post