Why is this important in remote sensing?1)Determines the spectral signal that can be remotely sensed (more absorbed energy, the less reflected to sensed). These important terms are further explained in the course textbook. To see this page as it is meant to appear, please enable your Javascript! In most of the cases, the Source of energy is the Sun. The sensor is a remote device to collect and record the electromagnetic radiation. It is important to note how small a portion of the electromagnetic spectrum is represented by the visible region. Wavelength Regions of Electromagnetic Spectrum used in Remote Sensing. Principles of Remote Sensing - Centre for Remote Imaging, Sensing and Processing, CRISP. The energy of photon is. Optical remote sensing satellites use reflected light to detect electromagnetic energy on the Earth’s surface. DMPQ- “The revolt of 1857 led to far-reaching changes in the system of administration and the policies of the British government.” Elucidate. A good number of studies carried over nearly three decades testifies the role of remote sensing in soil related studies. http://lasp.colorado.edu/cassini/education/Electromagnetic%20Spectrum.htm. Humans accomplish this task with aid of eyes or by the sense of smell or hearing; so, remote sensing is day-today business for people. The infrared region can be divided into two categories based on their radiation properties - the reflected IR, and the emitted or thermal IR. The amount of radiation from an object (called radiance) is influenced by both the properties of the object and the radiation hitting the object (irradiance). This radiation is just beyond the violet portion of the visible wavelengths, hence its name. Many times remote sensing will be helpful to predict the occurrence of natural hazards. There is a lot of radiation around us which is "invisible" to our eyes, but can be detected by other remote sensing instruments and used to our advantage. What is electromagnetic radiation (EMR)? All these technologies are integrated to act as one complete system in itself, known as Remote Sensing System. Common wavelengths of what we perceive as particular colours from the visible portion of the spectrum are listed below. The image is then interpreted to extract the informations about target. They are defined as such because no single primary colour can be created from the other two, but all other colours can be formed by combining blue, green, and red in various proportions. Detection and discrimination of objects or surface features means detecting and recording of radiant energy reflected or emitted by objects or surface material. For most purposes, the ultraviolet or UV portion of the spectrum has the shortest wavelengths which are practical for remote sensing. DMPQ- Give historical background of Public account committee. Remote sensing is very important to physical geography. DMPQ- Write an essay about the evolution of Paintings during Mughal period. If they did, then they would have to be cooled (and kept very cold during use), which would be very impractical. Trace the sequence of events during French revolution. • EMR is characterized by wavelength and frequency. Although we see sunlight as a uniform or homogeneous colour, it is actually composed of various wavelengths of radiation in primarily the ultraviolet, visible and infrared portions of the spectrum. The next portion of the spectrum of interest is the infrared (IR) region which covers the wavelength range from approximately 0.7 µm to 100 µm - more than 100 times as wide as the visible portion! Remote Sensing: Introduction and Basic Concepts Basic concepts of remote sensing D Nagesh Kumar, IISc, Bangalore 3 M1L1 Fig. Violet: 0.4 - 0.446 µmBlue: 0.446 - 0.500 µmGreen: 0.500 - 0.578 µmYellow: 0.578 - 0.592 µmOrange: 0.592 - 0.620 µmRed: 0.620 - 0.7 µm. 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