---
title: "Short note: Remote sensing process, applications"
subject: "Surveying II"
chapter: 7
key: "semester_4/surveying_ii:remote-sensing-process-applications"
source: https://www.bctengineer.com/q/semester_4/surveying_ii/remote-sensing-process-applications
site: BCT Engineering
---

# Short note: Remote sensing process, applications

Surveying II · Chapter 7: Photogrammetry and Remote Sensing

- Asked in: 2080 Chaitra, 4 marks
- Video: [Remote sensing//Advanced Surveying//Surveyor grade2](https://www.youtube.com/watch?v=BAgAAiKLARE) — CEekers
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_4/surveying_ii/remote-sensing-process-applications
- Whole chapter: https://www.bctengineer.com/md/semester_4/surveying_ii/chapter-7

## Question

Briefly explain remote sensing process. What are the application of remote sensing in civil engineering?

## Short answer

Remote sensing obtains Earth surface information by recording reflected/emitted energy from a distance. Process: energy source, atmospheric interaction, surface interaction, sensor recording, transmission, processing, and application. In civil engineering, it is used for land use mapping, route and site selection, flood studies, hazard mapping, and environmental impact assessment.

## Answer

#### Remote sensing process
Remote sensing is the collection of information about the Earth's surface without touching it. The process has these stages:

```text
 Sun --> Atmosphere --> Target --> Atmosphere --> Sensor
 (A)       (B)          (C)          (B)          (D)
                                                   |
        Ground station <-- transmission <----------+
              |
        Processing & analysis --> Application
```

1. **Energy source (A):** the sun (passive) or the sensor (active) provides electromagnetic energy.
2. **Radiation and atmosphere (B):** energy travels to the target and back, and is partly absorbed and scattered by the atmosphere.
3. **Interaction with the target (C):** the surface reflects, absorbs or emits energy according to its spectral signature (e.g. vegetation, water, soil).
4. **Recording by the sensor (D):** satellite or aircraft sensors record the energy as images.
5. **Transmission and reception:** the data are sent to a ground station.
6. **Processing and interpretation:** corrections, enhancement and classification; visual or digital interpretation.
7. **Application:** the information is used in maps, reports and decisions.

#### Applications in civil engineering
- Land use and land cover mapping; urban growth monitoring.
- Route and site selection for roads, canals, dams, bridges and pipelines.
- Water resources, flood mapping, catchment and watershed studies.
- Geological and landslide hazard mapping, soil mapping.
- Disaster assessment after earthquakes and floods.
- DEM and contour generation; environmental impact studies.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Which sequence is right?
   A. Sensor, target, source
   B. Energy source, atmosphere, target, sensor, transmission, processing, application
   C. Processing, source, target
   D. Target, application, source
   Answer: B. The chain runs from energy source to application. (Key point: Process sequence)

2. What does the atmosphere do?
   A. Creates the energy
   B. Records images
   C. Nothing
   D. Partly absorbs and scatters the energy
   Answer: D. It affects energy going to and from the target. (Key point: Atmosphere)

3. Target interaction depends on:
   A. Sensor colour
   B. Spectral signature of the surface
   C. Satellite name
   D. Orbit speed
   Answer: B. Vegetation, water and soil reflect/absorb differently. (Key point: Spectral signature)

4. A civil engineering application:
   A. Concrete mixing
   B. Beam design
   C. Welding
   D. Route/site selection and landslide hazard mapping
   Answer: D. Imagery supports route, site, hazard and water studies. (Key point: Application)

## Close variants set in other exams

- [Remote sensing, types, applications](https://www.bctengineer.com/question.md?key=semester_4%2Fsurveying_ii%3Aremote-sensing-types-application-civil) — Surveying II, chapter 7, asked 3×

## Related in Surveying II

- [Short note: Applications of remote sensing](https://www.bctengineer.com/question.md?key=semester_4%2Fsurveying_ii%3Aremote-sensing-applications) — Surveying II, chapter 7, asked 15×
- [Short note: Types of remote sensing](https://www.bctengineer.com/question.md?key=semester_4%2Fsurveying_ii%3Aremote-sensing-types-application) — Surveying II, chapter 7, asked 2×

## Related in other subjects

- [Scope and importance of geology in civil engineering](https://www.bctengineer.com/question.md?key=semester_3%2Fengineering_geology_i%3Ascope-and-importance-of-geology) — Engineering Geology I, chapter 1, asked 24×
- [Important properties of civil engineering materials](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aimportant-properties-civil-materials) — Civil Engineering Materials, chapter 1, asked 8×
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- [Classification of civil engineering materials](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aclassification-civil-materials) — Civil Engineering Materials, chapter 1, asked 2×