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Savita told her friend (a) that she worked as a typist in a store. She (b) came home every afternoon. It was Saturday (c) that day so she (d) was off early. (e) She further said that she  had an appointment with the doctor too.

Price of leveling per metre = Rs.2.50

Total price of leveling the plot = Rs.4000

Area of plot = 4000 ÷ 2.50

= 160 m

The area of rectangle plot is 160 m

Area of rectangle = L × B

160. = 80 × B

Breadth. = 160/80

= 2m

The breadth of rectangular plot is 2 m .

Perimeter of rectangle = 2(L+B)

= 2 ( 80+2)

= 2 × 82

= 164 m

• The carrier on which sensors are fixed for data collection is known as platform. 
• The platforms where cameras are placed: aircraft, bai loons, cranes. 
• The platform where sensors are placed: satellites. 

1. Spatial data 

2. Attributes

Based on the source of energy, remote sensing can be classified into active remote sensing and passive remote sensing.

Active remote sensing : Remote sensing made with the aid of artificial source of energy radiating from the sensor is known as active remote sensing.

Eg : flash in camera Passive remote sensing: Remote sensing made with the help of solar energy is known as passive remote sensing. In this, the sensors do not emit energy by it self.

1. Spatial date

2. Attributes

• Spatial data 
• Attribute data

• The instruments used for data collection through remote sensing are called sensors. 
• Sensors work with the help of electromagnetic radiations. Sensors record the electromagnetic radiations emitted or reflected by objects. 
• Examples are camera and scanner. 

• Number of students 
• Number of teachers 
• Number of classrooms
• School building is single or multi-storied. 

Overlay analysis

• Statement is wrong.
• Stereoscope is the instrument used for getting three-dimensional view from aerial photographs.
• Aerial photos with overlap alone can provide three- dimensional view.

Network analysis of GIS can be made use for the study tour. Network analysis can be useful for planning study tour in the following ways.

i. To identify the route with hospitals, hotels and petrol pumps on the way. 

ii. To identify the easiest and less congested roads from one place to another. 

iii. Plan maximum number of attractive destinations in the available time.

iv. Help to bring accident victim to a suitable hospital through less congested roads.

1. To conduct thematic studies. 

2. To represent geographical features spatially.

In each aerial photograph 60 percent of the places depicted in the adjacent photo is included. This is termed as the overlap in aerial photos. This is done for ensuring continuity and to obtain three-dimensional vision using a stereoscope.

a) Not stereo pair Two adjacent photographs with overlap is the stereo pair 

b) 63, 65

• Helps in setting three-dimensional view from aerial photos 
• To get the synoptic view of an area and to identify the undulations of the terrain.

Stereo pair of a pair of aerial photos with over-lap.

Stereo pair is two aerial photographs of adjoining areas. Whereas the instruments used for obtaining a three-dimensional view from the stereo pairs is called stereoscope.

Photography is the invention which paved the way for a great change in data collection in the 19th century.

• For collecting data about the extent of crops and spread of pest attacks.
• For understanding land use of an area.
• To locate places with greater ground water potential.
• For monitoring of drought and flood. 

Answer: Virulent gene

• To maintain continuity of aerial photographs.
• To ensure three-dimensional view 
• To view a region as a whole. 
• To distinguish the heights and depressions of the earth’s surface.

Each aerial photograph covers about 60 percent area of the adjacent photographs also. This is called overlap of aerial photographs.

Its advantages are:

• to maintain continuity of aerial photographs
• to ensure three-dimension view using a stereoscope.
• to view a region as a whole 
• to distinguish the heights and depressions of the earth’s surface.

i. In each aerial photograph, nearly 60% of the places depicted in the adjacent photos is included. This is known as overlap in aerial photographs.

ii. Stereo pair 

iii. When viewed through stereoscope, stereo pair gives a three-dimensional view. This helps in the analysis of aerial photographs. Ensures continuity of the aerial photographs.

In each aerial photograph, nearly 60% of the places depicted in the adjacent photo is included. This is done to ensure continuity and to obtain three dimensional view. This is termed as the overlap in aerial photos. Only photos with overlap can give three dimensional views.

Its advantages are :

• To ensure continuity of aerial photographs.
• To obtain three dimensional view 
• For a synoptic view of the area. 
• Help in understanding the undulations of the terrain. 

• The shaking of the aircraft affects the quality of photographs.
• Open space is needed for the takeoff and landing of planes.
• Not practical for taking photographs of vast and extensive regions.
• Costly to land the aircraft frequently for refuelling.

Spectral signature – Reflection of electromagnetic radiation-Physical property of objects.

Spatial resolution – Detects the smallest object Sensor

Sun-synchronous satellite – Polarorbiting -IRS

Geostationary satellite – Moves along with the rotation of earth-INSAT

In year 1960 onwards was data collection using satellite remote sensing started.

1. Overlap – definition 

2. It’s importance

1. i) Overlap

ii) Stereo pair 

iii) Stereoscope 

2. i) Each aerial photograph includes about 60% of the adjacent photograph

ii) Two adjacent aerial photos with overlap – stereo pair 

iii) Stereoscope is the instruments to get three-dimensional view from stereo pair

INSAT satellites are geostationary satellites. On the other hand, IRS are sun synchronous satellites.

1. Satellite remote sending 

2. i) Spread of forest fire 

ii) To detect natural calamities

iii) Landuse studies 

iv) Resources mapping

In this problem random variable is L

L can be 1,2,..............

P{L = 1} = 1/2

P{L = 2} = 1/4

P{L = 3} = 18

H{L} = 1/2log₂1/(1/2) + 1/4log₂1/(1/8) + ..... = 0 + 1 x 1/2 + 2 x 1/4 + 3 x 1/8 + ...

[Arithmatic gemometric series summation]

= 2/(1 - 1/2) + (1/2 x 1)/(1 - 1/2)² = 2

a) Surface of the earth-camera-covers small areas 

b) Aircraft/Balloon-Camera-covers extensive area

c) Satellite – Scanner-Cover very large aerial extent.

a. Captures continuous photographs of the places over which the aircraft passes.

b. Gathers information using sensors fitted in artijicial satellites.

Satellite remote sensing

1. Altitude

Geostationary – 36000 km

Sun-synchronous – 800-950 km

2. Revolution

Geostationary: with the speed of rotation of earth Sun-synchronous: Polar-orbiting

3. Use

Geostationary: Climate studies, telecommunication

Sun-synchronous: Remote sensing

The geostationary satellites of India are included in the series of INSAT.

Aerial remote sensing

• Orbit the earth at a height of about 36000 km.
• Positioned in the equatorial plane.
• As they move according to the orbital velocity of the earth, they always face the same region of the earth.
• One-third of the globe is brought under its observational limit.
• Constant data collection of one part of the earth is possible.
• Useful for understanding changes in weather conditions and for telecommunication.

• The process of collecting information using sensors fitted on artificial satellites is called satellite remote sensing. 
• Sensors in artificial satellites are known as ‘scanner’. 

1. Geostationary satellites 

2. Sun-synchronous satellites

• The sensors for collecting information are fixed on them
• Platform

• Estimation of loss due to flood. 
• Understanding the post-flood conditions of •rivers. 
• Assessment of the damages of the areas flooded. 
• Preparing flood predicting models by identifying areas vulnerable to flood. 

Geostationary satellites:

• Geostationary satellites are those with the same orbital velocity and direction as that of the earth.
• Orbit the earth at a height of about 36000 km
• Positioned in the equatorial plane.
• Since the orbits are at great heights, one-third of the globe is brought under their observational unit.
• Since they move according to the same orbital movement of the earth, they always face the same region of the earth.
• Constant data collection of any one part of the earth is possible.
• Used for understanding the differences in weather conditions and for telecommunications.
• Eg: INSAT satellites of India.

Sun-synchronous satellites:

• These are satellites that move at a very low height.
• The orbital height is below 1000 km from the earth’s surface.
• Move by traversing the north-south poles.
• Less observation limit.
• Come over a particular region at a fixed interval of days.
• Continuous collection of information about a region is possible.
• Used for Collecting information about natural resources, land use, and groundwater.
• Eg: IRS and Landsat