Voltage power and current, where 1 volt = 1 watt (of power) per 1 ampere (of current). This definition is equivalent to the more commonly used 'joules per coulomb'. Voltage or electric potential difference is denoted symbolically by , but more often simply as "V", for instance in the context of Ohm's or Kirchhoff's circuit laws. Electric potential differences between points can be caused by electric charge, by electric current through a magnetic field, by time-varying magnetic fields, or some combination of these three. A voltmeter can be used to measure the voltage (or potential difference) between two points in a
The Civil Wars: A Tree Is Best Measured When It Is Down and a principal writer was Lebanese poet Etel Adnan, though the collage-like libretto incorporated a diverse collection of texts. Bryars set a speech by Marie Curie, "I am among those who believe that science has a great beauty", a poem by Pope Leo XIII on the then-new art of photography, and a speech by an imaginary scientist in Jules Verne's "20,000 Leagues Under the Sea". The work was not completed or publicly performed, but Bryars incorporated a number of its arias into the later works "Effarene" and "On Photography". The Civil Wars: A Tree Is Best Measured When It Is