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.

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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

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Etymology

Origin of time constant

First recorded in 1890–95

Example Sentences

See Examples For:

time constant

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

From Washington Times ● Nov. 13, 2022

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

From Seattle Times ● Apr. 25, 2022

In Figure 21.44, does the graph indicate the time constant is shorter for discharging than for charging?

From Textbooks ● Aug. 12, 2015

Systematic investigations of the dynamics of electron injection for perylene-carboxylic-acid-sensitized titanium-oxide nanocrystals have shown that forward injection proceeds with about a 13 fs time constant, which is consistent with theoretical predictions.

From Nature ● Aug. 15, 2012

Under these circumstances the time constant of the instrument on short circuit is 0.0081 sec.

From Scientific American Supplement, No. 787, January 31, 1891 by Various