+91-9828-747676
Question
The zero graduation in prismatic compass is marked in the,
A.
North end of the circle
B.
In the West end of the circle
C.
In the South end of the circle
D.
In the East end of the circle
Answer ( Option C)

In the South end of the circle

Solution

Prismatic Compass : The prismatic compass is a magnetic compass in which there is a prism for taking observations.
• The prismatic compass is generally smaller in size than a surveyor’s compass.
• The prismatic compass consists of a circular box, about 85 to 100 mm diameter.
• The magnetic needle used in a prismatic compass is of broad in shape.
• An aluminum ring graduated in degrees and half degrees is directly attached with the needle.
• The graduations on the aluminium ring increase clockwise from 0º to 360º, with the zero of the graduations co-inciding with the south end of the needle, 90º graduation is at the west, 180º graduation at the north and 270º gradua-tion at the east as shown below in the figure.
• The prismatic compass is used for the determination of the whole circle bearings (W.C.B.) of the lines.
• Readings are taken through a prism attached to the box.
 
                                Fig: Prismatic Compass (Plan)
 
• When the line of sight is exactly towards the north, the reading observed is 0º.
• When it points exactly to the east, the reading observed is 90º.
• It may be noted that in a prismatic compass, the sighting of the object and the reading of the bearing are done simultaneously 

Popular Online Test Serie

Preparing students for success in a changing World.

RPSC-AE

RPSC-AE
RSSB-JE

RSSB-JE
SSC-JE

SSC-JE
RRB-JE/SSE

RRB-JE/SSE
RSEB-JE/AE

RSEB-JE/AE
DRDO CEPTAM -10 (STA-B)

DRDO CEPTAM -10 (STA-B)

ISRO Scientist Engineer

ISRO Scientist Engineer
View All

Online Classes

We care about our students

View More


banner
banner
banner
banner
banner
Online Classes
Register Now
Test Series
Register Now
Job Notification
Job Notification

Daily Quiz

RPSC-AE, RSMSSB-JE, SSC-JE, RRB-JE, PSU's