If the horizontal distance between the staff point and the point of observation is d, then the error due to curvature of earth is proportional to

Related MCQs

• When a staff is sighted through the telescope, a certain length of staff is intercepted by the stadia lines. The staff intercept varies with the distance at which the staff is held.
• In levelling, the correction for curvature (in metres) is equal, where D = Distance from the level to the staff reading in kilometres.
• It is required to find the difference in elevation between two points A and B. During levelling, it is found that the staff reading at B is more than the staff reading at A. It indicates that the point A is
• When the length of chain used in measuring distance is shorter than the standard length, the error in measured distance will be compensating error.
• As applied to staff readings, the corrections for curvature and refraction are respectively The above table shows a part of a level field book. The value of X should be
• When the effect of curvature is taken into account in levelling, the true staff reading is obtained by
• The fundamental requirement of the spiral curve is that its radius of curvature at any point shall vary inversely as the distance from the beginning of the curve.
• If the staff is not held vertical at a level¬ling station, the reduced level calculated from the observation would be
• When the effect of refraction is taken into account in levelling, the true staff reading is obtained by subtracting the correction for refraction from the observed staff reading.
• The distance by which the last point of the traverse falls short to coincide with the starting point is called the closing error.