Previous Year Question
In which of the following activities are Indian Remote Sensing (IRS) satellites used?
Assessment of crop productivity
Locating groundwater resources
Mineral exploration
Telecommunications
Traffic studies
Select the correct answer using the codes given below.
1, 2 and 3 only
4 and 5 only
1 and 2 only
1, 2, 3, 4 and 5
Correct Answer: A
Detailed Solution
Indian Remote Sensing satellites record electromagnetic energy reflected or emitted from the Earth’s surface and provide information related to natural resources.
Activity 1 is correct: Assessment of crop productivity.
Satellite images are used for estimating crop area, monitoring crop condition and forecasting production.
Crops are identified and monitored through their different spectral characteristics and the changes occurring in them over time.
Activity 2 is correct: Locating groundwater resources.
Remote sensing satellites do not directly observe underground water.
Potential groundwater zones are identified by studying features such as landforms, rock structures, faults, drainage systems and land use through satellite images.
Activity 3 is correct: Mineral exploration.
Satellite data are used for geological and geomorphological mapping.
Different spectral signatures of rocks, minerals and alteration zones assist in identifying potential mineral-bearing areas.
Activity 4 is not correct: Telecommunications.
IRS satellites are primarily used for Earth observation and resource mapping.
Telecommunication services are mainly provided through communication satellites such as INSAT and GSAT.
Activity 5 is not correct: Traffic studies.
In the context of the question, traffic studies were not an accepted major application of IRS satellites.
Navigation, communication and ground-based traffic data come under different systems.