Apr 12, 20202 min

Survey (181-200)

Updated: Apr 24, 2020

181. If f is the focal length, t is the angle of tilt, then the distance of isocentre on the

principal linefromthe principal point is f tan t/2


182. Parallax bar is used to measure parallax difference


183. As compared to mirror stereoscope, lens stereoscope is small in size


184. Setting out of bridges involves determination of length of centre line,position of piers


185.Boning rod-It is generally used in layout of trenches for sewers, pipe lines etc
 
Travelling rod-The horizontal piece can be moved along a graduated vertical staff
 
Sight rails-The horizontal, member of the cross head nailed to the posts
 
Batter boards-It is a flat, square,wooden board which is forced on the top of a pin anchored in ground. It is also known as slope rail.


186. In triangulation, the best shape of the triangle would be

isosceles with two base angles of 56° 14' each


187.Fathometer-Sounding instrument
 
Passometer-Distance measuring instrument
 
Tellurometer-Microwave instrument
 
Altimeter-Height measuring instrument


188. A closed compass traverse PQRS is run with a prismatic compass in a clock-wise direction:

The value of the included angle S is

-260°


189.The vertices of an would include: zenith, pole & heavenly body


190. The tilt displacement in an aerial photograph is radial from

isocentre point


191 Adjustment of surveying instruments-Bringing the various fixed parts of the instrument into proper relation with one another
 
Bowditch rule-Balancing the latitudes and departures
 
Triangulation-Measuring all the angles and the base line
 
Bessel's method-Solution of 3-point problem


192. If a quantity A has a weight of 3, then the weight of A/3 will be 27


193. In a parabolic vertical curve, the rising grade g = +0.80percentage and the falling grade g = -0.70%. The rate of change of grade is 0.05 per chain. The length of the vertical curve is 30 chains


194. Which one of the following indicates the correct relationship between the flying height (H), the focal length (f), the air base (B) and the photographic base (b)? B = BH/f


195.While measuring horizontal angles by the method of repetition with a theodolite, readings are taken on both the verniers. Which one of the following errors will be eliminated by reading both the verniers?

Error due to eccentricity of the centres


196. An angle-measuring instrument reading upto one-sixth of a degree on the main scale is equipped with a vernier having 19 main scale divisions divided into 20 parts. The correct least count for the instrument is 30 seconds


197. It is required to produce a small-scale map of an area in a magnetic zone by directly plotting and checking the work in the field itself. Which one of the following surveys will be most appropriate for this purpose? Plane Table


198

Clinometer-Angle measuring instrument
 
Pantograph-Plan enlarging instrument
 
Tellurometer-Microwave instrument
 
Ghat tracer-Gradient finding instrument
 


199. A 30 m metric chain is found to be 0.1 m too short throughout the measurement. If the distance measured is recorded as 300

m, then the actual distance will be 299.0 m


200. Offsets are lateral measurements made with respect to main survey lines


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