JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech II Year SURVEYING Previous Question Paper (March - 2022 - R15)

Errors in surveying arise from various sources and are broadly classified into three categories:

1. Instrumental Errors: These result from imperfections or faulty adjustments of the surveying equipment. Examples include a tape that is too long or short, a poorly adjusted level, or a compass needle that is not perfectly balanced. These can often be minimized by proper calibration and maintenance.
2. Personal Errors: These are caused by the human element, such as limitations in human senses (sight, touch, hearing) or lack of skill. Examples include incorrect reading of a scale, improper leveling of the instrument, or mistakes in recording data. These can be reduced by careful observation and repeated measurements.
3. Natural Errors: These arise from external environmental conditions such as temperature, humidity, wind, gravity, and refraction. For instance, the expansion or contraction of a steel tape due to temperature changes or the effect of atmospheric refraction on leveling. These are often corrected by applying mathematical corrections based on observed environmental conditions.

Given:

Since point C is to the north of AB, the angle is measured clockwise from the line BA. The back bearing of AB is S 68° 15′ W, which is 248° 15′ in whole circle bearing (WCB). The bearing of BC is calculated as follows:

Converting back to quadrantal bearing:

The deflection angle of CD is 25° 25′ to the right. The bearing of CD is calculated by adding the deflection angle to the bearing of BC:

Since the result exceeds 360°, subtract 360°:

Therefore, the bearing of CD is N 3° 00′ E.