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time constant

American  

noun

Electricity.
  1. the time required for a changing quantity in a circuit, as voltage or current, to rise or fall approximately 0.632 of the difference between its old and new value after an impulse has been applied that induces such a change: equal in seconds to the inductance of the circuit in henries divided by its resistance in ohms.


time constant British  

noun

  1. electronics the time required for the current or voltage in a circuit to rise or fall exponentially through approximately 63 per cent of its amplitude

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of time constant

First recorded in 1890–95

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

By changing the ratios of these oxides, the team achieved time constants ranging from 159 to 278 nanoseconds, or trillionths of a second.

From Science Daily

“Our results suggest that the optimal tempo for beat synchronization depends on the time constant in the brain,” Dr. Takahashi said.

From Washington Times

Nor is time constant, despite what the existence of an international standard might suggest.

From Seattle Times

Applying various sequences of radio pulses, the scanner measures the time constants, which depend on the water molecules' chemical environment and, hence, the tissue type.

From Science Magazine

Vibrational coherences typically decay with time constants in the picosecond range.

From Nature