lumen

Table of Contents

Introduction References & Edit History Quick Facts & Related Topics

Read Next

Highway Night Traffic Portland, drive, driving, car, automobile.

What's the Difference Between Speed and Velocity?

Abstract vector hi speed internet technology background

History of Technology Timeline

Binary Computer Code, Binary Code, Internet, Technology, Password, Data

How Does Wi-Fi Work?

Lab mouse using an optogenetics device

Optogenetics: Controlling the Brain with Light

Above the clouds 130 nautical miles below, astronaut Mark C. Lee floats freely without tethers as he tests the new Simplified Aid for Extravehicular Activity (EVA) Spacewalk Rescue (SAFER) system, Sept. 16, 1994. Space Shuttle Discovery, STS-64

Gravity: From Apples to the Universe

Discover

Queen Elizabeth II addresses at opening of Parliament. (Date unknown on photo, but may be 1958, the first time the opening of Parliament was filmed.)

All 119 References in “We Didn’t Start the Fire,” Explained

World Data Locator Map: Australia

Is Australia an Island?

A Factory Interior, watercolor, pen and gray ink, graphite, and white goache on wove paper by unknown artist, c. 1871-91; in the Yale Center for British Art. Industrial Revolution England

Inventors and Inventions of the Industrial Revolution

An ancient egyptian hieroglyphic painted carving showing the falcon headed god Horus seated on a throne and holding a golden fly whisk. Before him are the Pharoah Seti and the goddess Isis. Interior wall of the temple to Osiris at Abydos, Egypt.

11 Egyptian Gods and Goddesses

Law legal system crime concept with gavel and scales of justice with books in the background. (mallet, judicial system).

What Are the Differences Between First-, Second-, and Third-Degree Murder?

Cathedrale St.Jean in Lyon, France has a 14th-century astronomical clock that shows religious feast days till the year 2019; Perpetual Calendar

Ten Days That Vanished: The Switch to the Gregorian Calendar

Young boys working in a thread spinning mill in Macon, Georgia, 1909. Boys are so small they have to climb onto the spinning frame to reach and fix broken threads and put back empty bobbins. Child labor. Industrial revolution

The Rise of the Machines: Pros and Cons of the Industrial Revolution

lumen: References & Edit History

More Articles On This Topic

Assorted References

light flux
- In optics: General relations
luminous intensity
- In luminous intensity

Article Contributors

Primary Contributors

The Editors of Encyclopaedia Britannica

Other Encyclopedia Britannica Contributors

Article History

Type	Description	Contributor	Date
	Add new Web site: DigitalCommons at University of Nebraska - Lincoln - Light and Its Measurement (PDF).	Gloria Lotha	Dec 27, 2024
	Add new Web site: Energy.Gov - Lumens and the Lighting Facts Label.	Gloria Lotha	Oct 06, 2023
	Add new Web site: Energy.gov - Energy 101: Lumens.	Emily Rodriguez	Jun 27, 2017
	Article added to new online database.	The Editors of Encyclopaedia Britannica	Jul 20, 1998