Search results
- The changing electric and magnetic fields in light are similar to the waves that can be set up in a quiet pool of water. In both cases, the disturbance travels rapidly outward from the point of origin and can use its energy to disturb other things farther away.
Light is called an 'electromagnetic wave' for historical reasons* in the following sense: It turned out that the effects of visible light and other radiation can be calculated using Maxwell's equations, which are also used to model the behaviour of electrically charged particles. This was an instant of a successful unification and it hasn't ...
Solar radiation provides light for photosynthesis, which supports the entire ocean ecosystem. The energy reaching Earth from the sun is a form of electromagnetic radiation, which is represented by the electromagnetic spectrum (Figure 6.5.1). Electromagnetic waves vary in their frequency and wavelength.
Oct 15, 2004 · A scuba diver in the open ocean discovers she is immersed not only in water, but also in an ethereal blue light. Seawater absorbs light much more strongly than air does, but visible light is made up of a rainbow of different wavelengths, each perceived by us as a different color.
Radiant energy from the sun is important for several major oceanic processes: Climate, winds, and major ocean currents are ultimately dependent on solar radiation reaching the Earth and heating different areas to different degrees. Sunlight warms the surface water where much oceanic life lives.
- Overview
- Light as electromagnetic radiation
- Electric and magnetic fields
- Maxwell’s equations
In spite of theoretical and experimental advances in the first half of the 19th century that established the wave properties of light, the nature of light was not yet revealed—the identity of the wave oscillations remained a mystery. This situation dramatically changed in the 1860s when the Scottish physicist James Clerk Maxwell, in a watershed the...
In spite of theoretical and experimental advances in the first half of the 19th century that established the wave properties of light, the nature of light was not yet revealed—the identity of the wave oscillations remained a mystery. This situation dramatically changed in the 1860s when the Scottish physicist James Clerk Maxwell, in a watershed the...
The subjects of electricity and magnetism were well developed by the time Maxwell began his synthesizing work. English physician William Gilbert initiated the careful study of magnetic phenomena in the late 16th century. In the late 1700s an understanding of electric phenomena was pioneered by Benjamin Franklin, Charles-Augustin de Coulomb, and others. Siméon-Denis Poisson, Pierre-Simon Laplace, and Carl Friedrich Gauss developed powerful mathematical descriptions of electrostatics and magnetostatics that stand to the present time. The first connection between electric and magnetic effects was discovered by Danish physicist Hans Christian Ørsted in 1820 when he found that electric currents produce magnetic forces. Soon after, French physicist André-Marie Ampère developed a mathematical formulation (Ampère’s law) relating currents to magnetic effects. In 1831 the great English experimentalist Michael Faraday discovered electromagnetic induction, in which a moving magnet (more generally, a changing magnetic flux) induces an electric current in a conducting circuit.
Faraday’s conception of electric and magnetic effects laid the groundwork for Maxwell’s equations. Faraday visualized electric charges as producing fields that extend through space and transmit electric and magnetic forces to other distant charges. The notion of electric and magnetic fields is central to the theory of electromagnetism, and so it requires some explanation. A field is used to represent any physical quantity whose value changes from one point in space to another. For example, the temperature of Earth’s atmosphere has a definite value at every point above the surface of Earth; to specify the atmospheric temperature completely thus requires specifying a distribution of numbers—one for each spatial point. The temperature “field” is simply a mathematical accounting of those numbers; it may be expressed as a function of the spatial coordinates. The values of the temperature field can also vary with time; therefore, the field is more generally expressed as a function of spatial coordinates and time: T(x, y, z, t), where T is the temperature field, x, y, and z are the spatial coordinates, and t is the time.
In the early 1860s, Maxwell completed a study of electric and magnetic phenomena. He presented a mathematical formulation in which the values of the electric and magnetic fields at all points in space can be calculated from a knowledge of the sources of the fields. By Faraday’s time, it was known that electric charges are the source of electric fie...
For a review of wavelength and wave frequency, see Wave and Wave Properties. Electromagnetic radiation occurs in packets of energy called photons. A photon behaves like a wave and also like a particle. Because it is both a wave and a particle, describing the behavior of a photon is very complex.
People also ask
Why is light called an 'electromagnetic wave'?
How does sunlight affect the ocean?
What is light in the ocean?
Is light an electric or magnetic field?
What part of the electromagnetic spectrum is visible?
How does solar radiation affect the ocean?
Jun 10, 2024 · Sunlight warms the surface water where much oceanic life lives. Solar radiation provides light for photosynthesis, which supports the entire ocean ecosystem. The energy reaching Earth from the sun is a form of electromagnetic radiation, which is represented by the electromagnetic spectrum (Figure 6.5.1 6.5. 1).
