What do these conventional signs and symbols refer to in a topo sheet?
Tick (✓) the correct answers.
international boundary / forest boundary / tehsil boundary
unmetalled road / metalled road / telegraph line
tidal river / dry river / canal
- Tehsil boundary
- Unmetalled Road
- Tidal river
Quick Quiz 1
Topo sheets show the details of a very large area. True or False.
False, Topo sheets show the details of a very small area.
The 4° x 4° sheets are also called ............... sheets.
45 D/10 is an example of (quarter/quadrant) sheet.
Define grid square.
The eastings and the northings intersect to form a network of squares called the arbitrary grid system. Each square in the arbitrary grid system is called the grid square.
Why are the grid lines numbered?
The grid lines are numbered in order to locate places and features on topo sheets.
Quick Quiz 2
How much is the contour interval on a topo sheet?
The contour interval on a topo sheet is 20 metres.
The closely spaced contours indicate ............... slope.
Two hills separated by a pass is called a (ridge/saddle).
Profiles are drawn using contours. True or false?
How will you identify a spot height on a topo sheet?
The spot height is shown by a black dot followed by a number. The number shows the height of the spot in metres.
Quick Quiz 3
On the topo sheet, the squares with red outline show (temporary/permanent) settlements.
Name the different types of settlement on the basis of their shape.
The different types of settlement on the basis of their shape are:
............... settlement is found in hilly regions.
The drainage patterns are mentioned under land use. True or False?
When you interpret a topo sheet, under which head will you write about the major possible occupations in the region?
The major possible occupations in the region are written under economic activities.
Tick the correct answers
How many million sheets are drawn to cover the whole of India?
Which of these colours is used to draw contours?
Which of these is not a settlement pattern?
Which of these is not included in the marginal information about topo sheets?
- contour interval
- number of topo sheet
Parts of which of these states is shown in the topo sheet 45 D/10
Read clues & write names
The grid lines that run from east to west: ...............
The V-shaped contours show this relief feature: ...............
The side view of the cut of a relief feature:...............
Profile or Cross Section
This type of settlement is found along a railway track: ...............
The main stream that flows through Sirohi and Banas Kantha districts and shown on topo sheet 45 D/10 : ...............
Give reasons for the following
The quarter sheets are also called 1° x 1° sheets.
The extent of each quarter sheet is 1° of latitude and 1° of longitude. Thus, the quarter sheets are also called 1° x 1° sheets or degree sheets.
The distance between two successive contours indicate the slope of the land.
Contours are the lines, drawn on the map, which join the places that have same height above the mean sea level. The contours are marked with a number, known as contour value, which shows the height of the land in metres. Thus the difference between two successive contours (contour interval) depicts the difference in heights of two points on land. Thus, contour interval being same, widely spaced contours will depict a gentle slope while closely-spaced contours will depict a steep slope.
Answer the following questions
What are topo sheets?
The large-scale maps, prepared by the Survey of India, based on actual field surveys are called the topographical maps or topo sheets.
Name the groups into which the topo sheets are categorized.
The topo sheets are categorized into three main groups:
- Million sheets
- Quarter sheets
- Quadrant sheets
What are the differences between quarter and quadrant sheets?
|Quarter sheets||Quadrant sheets|
|1.||A million sheet is divided into 16 equal parts and each one is called Quarter sheet.||Quarter sheet is further sub-divided into 16 equal parts and each one is called Quadrant sheets.|
|2.||The extent of each quarter sheet is 1° of latitude and 1° of longitude.||The extent of each quadrant sheet is 1/4° of latitude and 1/4° of longitude.|
|3.||These are marked as A, B, C, D....P and are written as 45A, 45B, 45C.....45P.||These are numbered from 1 to 16 and are written as 45 A/1, 45 A/2...... 45 A/16.|
|4.||The scale of the sheet is 1 cm : 2.5 km.||The scale of the sheet is 2 cm : 1 km.|
Distinguish between grid and arbitrary grid system.
|Grid System||Arbitrary Grid System|
|1.||The network of latitudes and longitudes on maps is called Grid.||The grid formed by a set of vertical and horizontal lines drawn in red on a topo sheet is called arbitrary grid system.|
|2.||Grid System is drawn on Maps.||Arbitrary Grid System is drawn on Topographical Maps.|
|3.||The grid lines are called latitudes and longitudes.||The grid lines are called Northings and Eastings.|
|4.||The grid lines are represented in degrees.||The grid lines are represented in two digits such as 00, 01, 02, ... 99.|
Mention three features of arbitrary grid system.
Three features of arbitrary grid system are:
- The south-west corner or the bottom-left corner of topo sheet is always taken as the starting point or the point of reference for the grid.
- The vertical grid lines, drawn from north to south, are called the eastings. The eastings are so called because they lie towards the east of the south-west corner.
- The horizontal grid lines, drawn from east to west, are called the northings. The northings are so called because they lie towards the north of the south-west corner.
Define contour and contour interval.
Contour — Contours are lines, drawn on a map, which join the places that have the same height above the mean sea level.
Contour Interval —The difference between the values of any two successive contours is known as the contour interval (vertical interval).
Write two characteristics of contours.
Two characteristics of contours are:
- They are shown in brown.
- They are marked with a number called the contour value. It shows the height of the land, in metres, above the mean sea level.
How will you identify steep slope, ridge and bench mark on a topo sheet.
Steep slope — It is shown by closely-spaced contours.
Ridge — It is shown by elliptical contours.
Bench Mark — It is shown by a black dot followed by BM and a number.
What are the factors suitable for the growth and development of a settlement?
The factors suitable for the growth and development of a settlement are:
- Fertile river valleys and plains
- Source of water
- Presence of market or industrial sites
- Connectivity (presence of roads and railways)
Give two examples of areas where compact settlements are found.
Two examples of areas where compact settlements are found are:
- Fertile Area
- Industrial area
Mention two information that you will include under drainage.
The two information that are included under drainage are:
- Drainage patterns
- Prominent water bodies
Which are the two roads that connect Abu city?
The two roads that connect Abu city are:
- Abu road (from the south-east)
- Oriya road (from north-east)