Difference between Prismatic compass and Surveyor’s compass in simple language.First of all, keep both the compasses in front of you then one by one start matching these differences or just conduct an experiment for a small irregular plot by using these compass and you could also learn wcb system and rb system. So give your best trial.
||Magnetic needle is of broad size.
||Magnetic needle is of edge type.
||Graduations (divisions) are in W.C.B system.
||Graduations are in R.B system.
||Graduated ring has attachment with needle.
||Graduated ring has attachment with box.
||Divisions(readings) are noted down with the help of prism as graduations are inverted.
||Divisions are noted down directly from top of glass.
||Reading and sighting can be done at the same time from same position.
||Reading and sighting can be done separately from different position.
||For holding, support(i.e. Tripod) are not compulsory.
||For holding, supports are compulsory.
|| Prism at viewing end.
|| No prism at viewing end, hence there is only a slit.
Help Needy One
Gradient shows the meeting of elevation points at one end with respect to depression points at other end.
Sometimes 1st year or 2nd year students got confused when they hear about 1 in 100. Here 1 represents vertical distance and 100 represents horizontal distance in mm or cm or foot or inch or meter or KM as per requirement.
Types of gradients generally used in railway are:-
- Ruling gradient:- the grade at which a single locomotive can easily pass out train without any additional efforts.
- pusher gradient:- the gradient at which more than one locomotives are used to push the train.
- Momentum gradient:- the gradient at which momentum is provided to locomotive at down grade to overcome steeper gradient.
- Station yard gradient:- these gradients are provided to drain out water.
Such gradients are provided only to haul the train.
If you found something wrong in this article please tell us, so that we can improve our knowledge base.
Plumb bob is a metal bob shaped like cone attached with string at the top circular surface. When freely suspended its bottom tip always points towards the gravity and shows the direction of vertical line.Plumb bob also used for centering of surveying instruments like dumpy level, theodolite, compass etc. Masons generally prefer plumb bob for the vertical alignment of walls.
||Whole Circle Bearing(WCB)
||Reduced(Quadrantal) Bearing System
||Bearings (angles) are taken towards clockwise direction from magnetic north.
||Bearing are always taken from magnetic north or south whichever is nearer.
||Bearings are always taken in clockwise direction.
||Bearings are taken in clockwise or anticlockwise direction.
||Bearings vary from 0° to 360°
||Bearings vary from 0° to 90°
||Ex:-N 89°45́ E, N 55° W, S 69° E, S 77° W
Bearing represents measurement of angles w.r.t clockwise(examples: S 77° W or N 89°45́ E) or anticlockwise( S 69° E and N 55° W) direction or angles w.r.t north direction in surveying, where angle simply represent a degree in geometry.
How to convert reduced bearing system to whole circle bearing?
Suppose we have given N43°E means bearing is from North towards East so we do nothing i.e. 43°(WCB).—–>FIRST QUADRANT
Suppose we have given S43°E means bearing is from South towards East so we subtract from 180° i.e. 180°-43°=137°(WCB).—–>SECOND QUADRANT
Suppose we have given S43°W means bearing is from South towards West so we add 180° i.e. 180°+43°=223°(WCB).—–>THIRD QUADRANT
Suppose we have given N43°W means bearing is from North towards West so we subtract from 360° i.e. 360°-43°=317°(WCB).—–>FOURTH QUADRANT.
Thanks for Visiting