Back Sight given Height of Instrument Calculator

✖Height of instrument is the vertical distance from the surface of earth to the collimation plane. It is also called as height of plane of collimation.ⓘ Height of Instrument [HI]			+10% -10%
✖Reduced level is the vertical distance between a survey point and the adopted level datum.ⓘ Reduced Level [RL]			+10% -10%

✖Back Sight is the sight or reading taken towards the back or towards a known elevation.ⓘ Back Sight given Height of Instrument [BS]

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Formula

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Back Sight given Height of Instrument

Formula

`"BS" = "HI"-"RL"`

Example

`"36m"="65m"-"29m"`

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Back Sight given Height of Instrument Solution

STEP 0: Pre-Calculation Summary

Formula Used

Back Sight = Height of Instrument-Reduced Level
BS = HI-RL
This formula uses 3 Variables

Variables Used

Back Sight - (Measured in Meter) - Back Sight is the sight or reading taken towards the back or towards a known elevation.
Height of Instrument - (Measured in Meter) - Height of instrument is the vertical distance from the surface of earth to the collimation plane. It is also called as height of plane of collimation.
Reduced Level - (Measured in Meter) - Reduced level is the vertical distance between a survey point and the adopted level datum.

STEP 1: Convert Input(s) to Base Unit

Height of Instrument: 65 Meter --> 65 Meter No Conversion Required
Reduced Level: 29 Meter --> 29 Meter No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

BS = HI-RL --> 65-29

Evaluating ... ...

BS = 36

STEP 3: Convert Result to Output's Unit

36 Meter --> No Conversion Required

FINAL ANSWER

36 Meter <-- Back Sight

(Calculation completed in 00.004 seconds)

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Created by Chandana P Dev

NSS College of Engineering (NSSCE), Palakkad

Chandana P Dev has created this Calculator and 500+ more calculators!

Verified by Ishita Goyal

Meerut Institute of Engineering and Technology (MIET), Meerut

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< 17 Levelling Calculators

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Difference in Elevation between Ground Points in short lines under Trigonometric levelling

Go Elevation Difference = Distance between Points*sin(Measured Angle)+Height of point A-Height of point B

Distance between Two points under Curvature and Refraction

Go Distance between Two Points = (2*Earth Radius in km*Error due to Curvature+(Error due to Curvature^2))^(1/2)

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Angle of Dip for Compass Surveying

Go Dip Angle = Distance between Two Points/Earth Radius in km*(180/pi)

Error Due to Curvature Effect

Go Error due to Curvature = Distance between Two Points^2/(2*Earth Radius in km)

Distance to Visible Horizon

Go Distance between Two Points = sqrt(Height of Observer/0.0673)

Permissible Closing Error for Rough Levelling

Go Closing Error = 100*sqrt(Distance between Two Points)

Permissible Closing Error for Ordinary Levelling

Go Closing Error = 24*sqrt(Distance between Two Points)

Permissible Closing Error for Accurate Levelling

Go Closing Error = 12*sqrt(Distance between Two Points)

Permissible Closing Error for Precise Levelling

Go Closing Error = 4*sqrt(Distance between Two Points)

Reduced Level given Height of Instrument

Go Reduced Level = Height of Instrument-Back Sight

Back Sight given Height of Instrument

Go Back Sight = Height of Instrument-Reduced Level

Height of Instrument

Go Height of Instrument = Reduced Level+Back Sight

Correction on Refraction Error

Go Refraction Correction = 0.0112*Distance between Two Points^2

Height of Observer

Go Height of Observer = 0.0673*Distance between Two Points^2

Combined Error Due to Curvature and Refraction

Go Combined Error = 0.0673*Distance between Two Points^2

Back Sight given Height of Instrument Formula

Back Sight = Height of Instrument-Reduced Level
BS = HI-RL

What is Back Sight?

A Back Sight is a surveying term that refers to the measurement of a previously established point's elevation to determine the difference in elevation between it and a new point.

What is Levelling?

Levelling is a process of determining the height of one level relative to another. It is used in surveying to establish the elevation of a point relative to a datum, or to establish a point at a given elevation relative to a datum.

How to Calculate Back Sight given Height of Instrument?

Back Sight given Height of Instrument calculator uses Back Sight = Height of Instrument-Reduced Level to calculate the Back Sight, Back Sight given Height of Instrument is sight or reading taken to known elevation (generally to bench mark). Back Sight is denoted by BS symbol.

How to calculate Back Sight given Height of Instrument using this online calculator? To use this online calculator for Back Sight given Height of Instrument, enter Height of Instrument (HI) & Reduced Level (RL) and hit the calculate button. Here is how the Back Sight given Height of Instrument calculation can be explained with given input values -> 36 = 65-29.

FAQ

What is Back Sight given Height of Instrument?

Back Sight given Height of Instrument is sight or reading taken to known elevation (generally to bench mark) and is represented as BS = HI-RL or Back Sight = Height of Instrument-Reduced Level. Height of instrument is the vertical distance from the surface of earth to the collimation plane. It is also called as height of plane of collimation & Reduced level is the vertical distance between a survey point and the adopted level datum.

How to calculate Back Sight given Height of Instrument?

Back Sight given Height of Instrument is sight or reading taken to known elevation (generally to bench mark) is calculated using Back Sight = Height of Instrument-Reduced Level. To calculate Back Sight given Height of Instrument, you need Height of Instrument (HI) & Reduced Level (RL). With our tool, you need to enter the respective value for Height of Instrument & Reduced Level and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.

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