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

“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 each time constant τ , the voltage falls by 0.368 of its remaining initial value, approaching zero asymptotically.

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

But before that time constant structural modification was in progress.

From A Wanderer in Venice by Morley, Harry