I. Choosethe correct answer:
1. Maps created by using aerialphotographs are called ___ maps Ortho photo
2. The Object under study is known as_________ Target
3. The device to detect the ElectroMagnetic Radiation is _____ Sensor
II. Matchthe following
| 1. Ground Survey | Many Months |
| 2. Remote Sensing | Short span of time |
| 3. Hot air balloon | French Map makers |
| 4. Airplanes | Systematic aerial images |
| 5. TIROS | USA |
II. Shortanswers:
1.What is meant by remote sensing?
Remote – far away
Sensing – getting information
Remote Sensing can be defined as thecollection of data about an object from a distance.
2.What are the disadvantages of ground survey?
The disadvantages of ground survey
Ground survey of resources is hinderedby dense forests, rugged terrain, sandy deserts and unpredictable weather.
It takes many months to study.
3.Mention the basic components of remote sensing.
The four basic components of a remotesensing system are
- Target,
- Energy source,
- Transmission path and
- a Sensor.
4.Define GIS.
Geographical Information System (GIS)is a systematic integration of Computer Hardware, Software and Spatial Data,for capturing, storing, displaying, updating, manipulating and analyzing allforms of geographically referenced data.
5.Mention any two applications of GIS.
- Explorationand mining companies use GIS to find prospective areas for exploration andmining.
- PowerCompanies use GIS to monitor and analyse the electricity load for particulararea.
- Transportcompanies use GIS to locate shortest routes for delivering goods and to savetime.
6.What are the uses of GPS?
The usesof GPS
- Surveying,Map-making, Navigation the main civilian use of GPS.
- Navigation,Target tracking, Missile Search and rescue are the main military use of GPS.
- GPS auseful tool for commerce, scientific uses, tracking and surveillance.
- Farmers,surveyors, geologists perform their work more efficiently, safely, economically.
IV. Answerin a paragraph:
1.Write about Remote Sensing Technology.
Remotesensing can be defined as the collection of data about an object from adistance.
- Geographersuse the remote sensing as a tool to monitor or measure phenomena on the Earth’slithosphere, hydrosphere, atmosphere and biosphere.
- Remotesensing is done with the help of mechanical devices known as sensors.Thesesensors are positioned in helicopters, planes and satellites.
- Sensorsrecord electromagnetic energy that is reflected back and radiated from theobject on the earth surface. Hence, the most effective technology to gatherinformation on any part of the earth within a short span of time.
2.Explain the various components of remote sensing.
Componentsof Remote sensing:-
The four basic components of Remotesensing system are target, energy source, transmission path and a sensor.
The target is an object or materialthat is being imaged. Work together to measure and record information about thetarget.
Withoutphysical contact.
The energy source provideselectromagnetic energy to the target.
Classifiedinto two
- Passive System (that is sun, irradiance fromearth’s materials)
- Active System (that is energy sources such asradar).
- Theelectromagnetic radiation interacts with the target, depending on theproperties of the target.
- Transmitinformation from the target to the sensor.
- Sensor isa device to detect the Electro Magnetic Radiation can be classified on thebasis of energy received into Passive sensors and Active sensors.
- Passivesensors detect natural radiation that is emitted or reflected by the object.For eg: Cameras
- Activesensors transmit their own signal and measure the energy that is reflected fromthe target for example Radar.
3.Explain the process involves in remote sensing technology
Processesinvolved in Remote Sensing:-
Sun is aEnergy Source (A) first requirement which provideselectromagnetic energy to the target of things.
Sunraysand Atmosphere (B) as the energy travels from its source to thetarget interact with, the atmosphere second time from the target to the sensor.
Sunraysand Objects on Earth (C) energy interacts with the target depending onthe properties of both the target and the radiation.
Recordingof Energy by the Sensor (D) after energy emitted from the target, thesensor collects and records the electromagnetic radiation.
Transmission,Reception and Processing (E) the energy recorded by the sensor has to betransmitted, and processed into an image (hardcopy and/or digital).
Interpretationand Analysis (F) the processed image is interpreted, to extractinformation about the target which was illuminated.
Application(G) the final process is achieved by applying the extractedinformation for better understanding.
4.What are the advantages of remote sensing?
Advantagesof Remote Sensing:-
- Thissystem provides a synoptic view of a wide area in a single frame.
- Remotesensing systems detect features that cannot be reached by human vision.
- Cheaperand rapid method of acquiring up to-date and continuous information.
- Helps theplanners for formulating policies and programs.
Enable the cartographers to prepare thematicmaps like geological maps, soil maps.