Definition of impedance in English:



  • The effective resistance of an electric circuit or component to alternating current, arising from the combined effects of ohmic resistance and reactance.

    • ‘Electric impedance tomography is a new imaging technique that is potentially capable of monitoring those imbalances.’
    • ‘The constant impedance is maintained despite changes in temperature and voltage by using two external resistors to hold the impedances for all the I / O pins, which can number hundreds in the larger parts.’
    • ‘If the load impedance is not equal to the transmission line impedance, the wattmeter will indicate the amount of reflected power.’
    • ‘This was because the coupling resistance value had inverse effects on the amount of current arriving and on the impedance of the neurite.’
    • ‘A high impedance probe for the spectrum analyzer is essential.’
    • ‘It may be expressed as IX, where X, the reactance, is the imaginary part of the impedance.’
    • ‘Each antenna features vertical polarization, with an impedance of 50 ohms.’
    • ‘This greatly minimizes crosstalk among signals and helps to balance the effective impedance of each line at high frequencies.’
    • ‘Note that impedance and reactance are both given in units of ‘ohms’ just like resistance.’
    • ‘The instrument must show the true rms value of the voltage across the measuring impedance.’
    • ‘In contrast, the configurations and sizes of the nozzles of the first and the second head members are identical, and their impedances are also the same.’
    • ‘When impedance is reached, the energy shuts off and a tone alerts OR staff members that fusion is complete.’
    • ‘An impedance matching circuit is provided for each signal-carrying wire pair of the first and second wire pair sets.’
    • ‘As the signal propagates down a path, the voltage magnitude is related to the effective impedance up to the point in the signal's flight.’
    • ‘Figure 3 shows the display when the cable is terminated in its characteristic impedance of 50 ohms.’
    • ‘The passive antenna elements are coupled to selectable impedance components.’
    • ‘The transponder alters the impedance of the tuned circuit in accordance with the coded pattern.’
    • ‘Electrical impedance spectroscopy is a method for studying the structure of organic and inorganic materials.’
    • ‘The technique is based on the principle that lean tissue has a higher electrical conductivity and a lower impedance rate than fat.’
    • ‘Will the electric impedance tomography technique be improved further?’


Impedance is a specialized electrical term (as defined above), while impediment is an everyday term meaning 'a hindrance or obstruction': a low-impedance power supply; interpreting his handwriting was an impediment to getting business done