Assertion: magnetic field's field line | /r/HasProperty | useful
Facets:
value: as a representation of magnetic fields
type: MANNER
Source sentences:
text: Field lines are useful as a representation of magnetic fields, allowing for many laws of magnetism (and electromagnetism) to be simplified and expressed in mathematical terms.
text: Field lines are a useful way to represent any vector field and can often be used to reveal sophisticated properties of that field quite simply.