Exams › GATE › Technical

A levelling is carried out to establish the reduced level (RL) of point R with respect to the benchmark (BM) at P. The staff readings taken are given below: Staff station P: BS = 1.655 m, RL = 100.000 m; Q: IS = 0.950 m, FS = 1.500 m; R: FS = 0.750 m. If the RL of P is +100.000 m, then the RL, in m, of R is

1. 103.355
2. 103.155
3. 101.455
4. 100.355

Correct answer: 103.355

Solution

In levelling, the height of instrument is obtained by adding the backsight to the known RL. The RL of R is then found by subtracting the foresight reading from the HI, giving 103.355 m.

Related GATE Technical questions

• If the number of sides of a closed traverse is increased from three to four, the sum of the interior angles increases by
• A surveyor observes a zenith angle of 93° 00' 00" during a theodolite survey. The corresponding vertical angle is
• A map is prepared with a scale of 1:1000 and a contour interval of 1 m. If the distance between two adjacent contours on the map is 10 mm, the slope of the ground between the adjacent contours is
• If the horizontal distance between a staff point and the point of observation is \(d\), the error due to the curvature of the Earth is proportional to
• A level instrument at a height of 1.320 m has been placed at a station having a reduced level (RL) of 112.565 m. The instrument reads \(-2.835\) m on a levelling staff held at the bottom of a bridge deck. The RL, in m, of the bottom of the bridge deck is
• A camera with a focal length of 20 cm fitted in an aircraft is used for taking vertical aerial photographs of a terrain. The average elevation of the terrain is 1200 m above mean sea level (MSL). What is the height above MSL at which the aircraft must fly in order to get aerial photographs at a scale of 1:8000?

⚔️ Practice GATE Technical free + battle 1v1 →