electromagnet

(noun)

A magnet which attracts metals only when electrically activated.

Related Terms

Examples of electromagnet in the following topics:

  • The Production of Electromagnetic Waves

    • Electromagnetic waves are the combination of electric and magnetic field waves produced by moving charges.
    • Electromagnetic radiation, is a form of energy emitted by moving charged particles.
    • The creation of all electromagnetic waves begins with a charged particle.
    • These and many more such devices use electromagnetic waves to transmit data and signals.
    • Electromagnetic waves are a self-propagating transverse wave of oscillating electric and magnetic fields.

  • Solenoids, Current Loops, and Electromagnets

    • Solenoids are important because they can create controlled magnetic fields and can be used as electromagnets.
    • Electromagnetism is the use of electric current to make magnets.
    • These temporarily induced magnets are called electromagnets.
    • Combining a ferromagnet with an electromagnet can produce particularly strong magnetic effects.
    • An electromagnet creates magnetism with an electric current.

  • Maxwell's Predictions and Hertz' Confirmation

    • Maxwell's prediction of the electromagnetic force was confirmed by Hertz who generated and detected electromagnetic waves.
    • The propogation of an electromagnetic wave as predicted by Maxwell and confirmed by Hertz.
    • The apparatus used by Hertz in 1887 to generate and detect electromagnetic waves.
    • An RLC circuit connected to the first loop caused sparks across a gap in the wire loop and generated electromagnetic waves.
    • Explain how Maxwell's prediction of the electromagnetic force was confirmed by Hertz

  • Photon Energies of the EM Spectrum

    • The electromagnetic (EM) spectrum is the range of all possible frequencies of electromagnetic radiation.
    • The electromagnetic (EM) spectrum is the range of all possible frequencies of electromagnetic radiation .
    • Maxwell's equations predicted an infinite number of frequencies of electromagnetic waves, all traveling at the speed of light.
    • This was the first indication of the existence of the entire electromagnetic spectrum.
    • The last portion of the electromagnetic spectrum was filled in with the discovery of gamma rays.

  • Energy and Momentum

    • Electromagnetic waves have energy and momentum that are both associated with their wavelength and frequency.
    • Electromagnetic radiation can essentially be described as photon streams.
    • Planck theorized that "black bodies" (thermal radiators) and other forms of electromagnetic radiation existed not as spectra, but in discrete, "quantized" form.
    • In other words, there were only certain energies an electromagnetic wave could have.
    • Relate energy of an electromagnetic wave with the frequency and wavelength

  • Ferromagnets and Electromagnets

    • There are two type of magnets—ferromagnets that can sustain a permanent magnetic field, and electromagnets produced by the flow of current.
    • In the second class of magnets—known as electromagnets—the magnetic field is generated through the use of electric current.
    • In an electromagnet the magnetic field is produced by the flow of electric current.
    • This is called a ferromagnetic-core or iron-core electromagnet.
    • A simple electromagnet consisting of a coil of insulated wire wrapped around an iron core.

  • Microwaves

    • Microwaves are electromagnetic waves with wavelengths ranging from one meter to one millimeter (frequencies between 300 MHz and 300 GHz).
    • Super high frequency (SHF) is the designation for electromagnetic wave frequencies in the range of 3 GHz to 30 GHz.
    • Microwaves are the highest-frequency electromagnetic waves that can be produced by currents in macroscopic circuits and devices.
    • The electromagnetic spectrum, showing the major categories of electromagnetic waves.
    • Distinguish three ranges of the microwave portion of the electromagnetic spectrum

  • Visible Light

    • Visible light is the portion of the electromagnetic spectrum that is visible to the human eye, ranging from roughly 390 to 750 nm.
    • Electromagnetic radiation in this range of wavelengths is often simply referred to as "light".
    • The human eye is insensitive to electromagnetic radiation outside this range.
    • The electromagnetic spectrum, showing the major categories of electromagnetic waves.
    • A small part of the electromagnetic spectrum that includes its visible components.

  • Radio Waves

    • Radio waves are EM (Electromagnetic)waves that have wavelengths between 1 millimeter and 100 kilometers (or 300 GHz and 3 kHz in frequency).
    • Radio waves are a type of electromagnetic (EM) radiation with wavelengths in the electromagnetic spectrum longer than infrared light .
    • Like all other electromagnetic waves, radio waves travel at the speed of light.
    • Electromagnetic waves also broadcast television transmission.
    • The electromagnetic spectrum, showing the major categories of electromagnetic waves.

  • Energy Transportation

    • Similarly we find that electromagnetic waves carry energy.
    • Electromagnetic radiation (EMR) carries energy—sometimes called radiant energy—through space continuously away from the source (this is not true of the near-field part of the EM field).
    • Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields .
    • The photon is the quantum of the electromagnetic interaction, and is the basic "unit" or constituent of all forms of EMR.
    • Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields.