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Key Terms

PhysicsKey Terms

electric field
a field that tells us the force per unit charge at all locations in space around a charge distribution
electromagnetic radiation (EMR)
radiant energy that consists of oscillating electric and magnetic fields
number of lumens per square meter, given in units of lux (lx)
increased or decreased light intensity caused by the phase differences between waves
unit of measure for luminous flux
luminous flux
rate at which light is radiated from a source
unit of measure for illuminance
magnetic field
the directional lines around a magnetic material that indicates the direction and magnitude of the magnetic force
Maxwell’s equations
equations that describe the interrelationship between electric and magnetic fields, and how these fields combine to form electromagnetic radiation
polarized light
light whose electric field component vibrates in a specific plane
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