line of force

American  

noun

Physics.

1. an imaginary line or curve in a field of force, as an electric field, such that the direction of the line at any point is that of the force in the field at that point.

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line of force British  

noun

1. an imaginary line representing a field of force, such as an electric or magnetic field, such that the tangent at any point is the direction of the field vector at that point

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line of force Scientific  

1. A line used to indicate the direction of a field, especially an electric or magnetic field, at various points in space. The tangent of a line of force at each point indicates the orientation of the field at that point. Arrows are usually used to indicate the direction of the force.

2. See Note at magnetism

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Etymology

Origin of line of force

First recorded in 1870–75

Example Sentences

The magnetic lines of force at the surface create many observable effects, including sunspots, which are dark regions where solar plasma cools and emits less light than surrounding areas.

From Scientific American

“The safety is the last line of force on the defense and I don’t feel like anything is getting past Chinn, to be honest,” Burns said.

From Seattle Times

Once a line of force begins, he keeps it going, even adding strength to it, until it meets an immovable object or exhausts itself in open space.

From The New Yorker

Her motives for reversing the line of force in “Salt” are no longer available to her.

From New York Times

This simple combination creates magnetic lines of force that corkscrew around the plasma, confining it as a smaller doughnut-within-the-doughnut.

From Economist