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Absorption is the method which energy of a photon is used by matter. Electromagnetic energy can be converted into internal energy of the absorbing matter. The absorption of light waves will not depend on the intensity of the light waves. However, in certain situations the medium changes its transparency dependency on the intensity of waves.

Absorbance indicates how much of the incident light was absorbed. Measurements of absorbance allow the identification of a substance via absorption spectroscopy. This is where the sample is illuminated from one side and the intensity of the light that exits from the sample at every direction is measured. Same examples of absorption spectroscopy in different arts of the spectrum are ultraviolet-visible spectroscopy, infrared spectroscopy and X-ray absorption spectroscopy. 

Applied Physics: Optics Questions

(a) Describe the terms of reflection, absorption, and transmission with suitable diagrams. Present and explain the relationship between reflection, absorption and transmission coefficients. Describe the differences between materials that are opaque translucent and transparents. (b) An optical fibre consists of a core of refrac

Absorption of heat

A sheet of acetate paper is wrapped around a clear glass container. A thermometer is placed inside the glass container and held at a distance of 20 cm from a 100 W light bulb. Four different color acetate papers are used (red, green, blue, yellow). If each color paper is held for 45 minutes from the light source, how should the

Sound Intensity with Tsunami Warning Sirens

Residents of Hawaii are warned of the approach of a tsunami by sirens mounted on the top of towers. Suppose a siren produces a sound that has an intensity level of 120 dB at a distance of 2.0 m. Treating the siren as a point source of sound, and ignoring reflections and absorption, find the intensity level heard by an observer

Lead tests

How do you test lead levels in water to give a quantitate result, not just whether lead is preasent or not? Where do you get lead testing equipment? Provide an equipment list, a list of chemicals and method. Note we have a colormeter at college.

Three basic types of spectra

Could you give a description of the three basic types of spectra. What are the circumstances under which each would be formed?

Microphone in ocean

A microphone in the ocean is sensitive to sounds emitted by porpoises. To produce a usable signal, sound waves striking the microphone must have an intensity of 10.7 dB. If porpoises emit sound waves with a power of 0.0491 W, how far can a porpoise be from the microphone and still be heard? Disregard absorption of sound waves by