Chapter 20

Question 1

When did Thomas Edison announce the successful development of incandescent lamp with a baked carbonized cotton thread filament?

Answer 1

December 21, 1879

Question 2

Branch of physics that relates to the properties of light and the function of vision

Answer 2

Optics

Question 3

It functions much like a simple, very crude camera.

Answer 3

Eye

Question 4

Rays of light pass through this transparent part of the eye.

Answer 4

Cornea

Question 5

Opening of the eye.

Answer 5

Pupil

Question 6

It surrounds the pupil.

Answer 6

Iris

Question 7

The inability to distinguish colors.

Answer 7

Color blindness

Question 8

Form of electromagnetic radiation that allows eye to see.

Answer 8

Light

Question 9

It is the energy radiated in the form of a wave caused by an electric field interacting with a magnetic field.

Answer 9

Electromagnetic Radiation

Question 10

Electromagnetic radiation behaves as a group of particles called ______.

Answer 10

Photons

Question 11

Speed of Light

Answer 11

186,000 miles per second or 300,000,000 meters per second

Question 12

Measured as the distance from one wave peak to another.

Answer 12

Wavelength

Question 13

The number of wave cycles per second measured in hertz.

Answer 13

Frequency

Question 14

On the electromagnetic radiation spectrum, give at least three groups that is not visible with the naked eye.

Answer 14

1. Cosmic Radiation
2. Gamma Rays
3. X-rays
4. Ultraviolet
5. Infrared Radiation
6. Microwaves
7. TV waves
8. Radio waves

Question 15

The part of electromagnetic radiation spectrum capable of exciting the retina and ultimately producing a visual sensation.

Answer 15

Visible light

Question 16

Wavelength of visible light range.

Answer 16

380 nm to 750 nm

Question 17

The amount of light incident on (striking) a surface.

Answer 17

Illuminance

Question 18

The amount of light leaving an object.

Answer 18

Luminance

Question 19

The ratio of reflected light versus the light striking the surface (illuminance).

Answer 19

Reflectance

Question 20

The ratio of light transmitted through the body versus the light illuminating the surface.

Answer 20

Transmittance

Question 21

The ratio of the light absorbed versus the light striking the surface.

Answer 21

Absorptance

Question 22

A body that transmits light through it without distorting the image.

Answer 22

Transparent

Question 23

A body that transmits light but obscures the image because the light is scattered.

Answer 23

Translucent

Question 24

It is the light that is widely spread or scattered.

Answer 24

Diffuse Light

Question 25

It is a strong, directional type of light. It is the type available on a cloudless, sunny day where shadows are well defined.

Answer 25

Direct Light

Question 26

The ability to distinguish and interpret different wavelengths of visible light.

Answer 26

Color perception

Question 27

A device that generates light.

Answer 27

Lamp

Question 28

It is a complete lighting unit, which consists of a lamp (or lamps), lamp socket(s), any lenses, refractors, or louvers, any ballast (or ballasts), and the housing.

Answer 28

Luminaire

Question 29

It is the luminaire less the lamp(s).

Answer 29

Light fixture

Question 30

The measure of the perceived power of light expressed in lumens (lm)

Answer 30

Luminous flux

Question 31

The SI unit of solid angular measure

Answer 31

Steradian (sr)

Question 32

SI unit of luminous intensity—that is, the power emitted by a light source in a particular direction

Answer 32

Candela (cd)

Question 33

One candela is equivalent to

Answer 33

One lumen per steradian

Question 34

The ratio of the light output of a light source (a specific lamp) to the electrical energy consumed (including the ballast if applicable) to produce that light source

Answer 34

Luminous efficacy

Question 35

Luminous efficacy is expressed in units of _____

Answer 35

lumens per watt of electric power (lm/W)

Question 36

This lamp emit visible light as a result of heating.

Answer 36

Incandescent Lamp

Question 37

These are a smaller, brighter, and more expensive version of the incandescent lamp.

Answer 37

Tungsten-halogen lamps

Question 38

It is the electricity passing through a gas such that it causes the gas to arc

Answer 38

Gaseous discharge

Question 39

It is composed of a tubular glass bulb that is covered with a thin phosphor coating on its inside surface.

Answer 39

Fluorescent lamp

Question 40

It produce a very bright light by discharging an arc when electrical current passes through a metal gas contained under high pressure in a glass bulb.

Answer 40

High-intensity discharge (HID) lamps

Question 41

These are lamps that combine the luminous efficiency of an HID lamp with the good color rendering capability of an incandescent lamp.

Answer 41

Blended lamps

Question 42

It refers to a type of lighting that uses light-emitting diodes (LEDs), organic light-emitting diode lights (OLEDs), or polymer light-emitting diodes (PLEDs), instead of traditional lighting sources that use an electrical filament or gas inside a glass bulb.

Answer 42

Solid-state lighting (SSL)

Question 43

Sometimes called general lighting, it provides uniform illumination throughout the space. It softens shadows on people’s faces and provides the illumination for color and texture

Answer 43

Ambient lighting

Question 44

It is the directional lighting used to emphasize a particular object or area.

Answer 44

Accent Lighting

Question 45

The light source that adds a quality of interest to the space.

Answer 45

Decorative Lighting

Question 46

It is required in the critical care and emergency spaces found in hospitals, nursing homes, and police, fire protection, and crisis management areas

Answer 46

Emergency Lighting

Question 47

It is part of the emergency lighting system. It enables normal activities to continue substantially unchanged.

Answer 47

Stand-by lighting

Question 48

The part of emergency lighting system that ensures the safety of people involved in a potentially hazardous process

Answer 48

Safety lighting

Question 49

It provides illumination to ensure that an escape route can be effectively identified and used in the case of failure of the normal lighting system

Answer 49

Escape lighting

Question 50

It is the part of the escape lighting system that includes illuminated signage used to provide clear directions for an emergency exit of building occupants

Answer 50

Exit lighting

Question 51

It is a luminaire that is hung with a cord, chain, or tube that enables it to be suspended from a ceiling or other support. It broadcasts light over the entire space.

Answer 51

Pendent

Question 52

It is a luminaire where a shielded light source directs its light to the ceiling, where it is reflected back to the space.

Answer 52

Uplight

Question 53

It is a luminaire that is usually attached to or recessed in the ceiling and emits a concentrated light downward.

Answer 53

Downlight

Question 54

A type of downlight that is a recessed, canister-shaped luminaire with a shielded lamp that emits light downward.

Answer 54

High hat

Question 55

These luminaires are mounted above the ceiling or behind a wall or other surface so that any visible projection of light is insignificant.

Answer 55

Recessed

Question 56

These are decorative, wall-mounted luminaires that provide ambient illumination.

Answer 56

Sconces

Question 57

Luminaires that are used in high-ceiling areas

Answer 57

High bay luminaires

Question 58

These luminaires are more compact. They are designed for use in low- to medium-ceiling areas.

Answer 58

Low bay luminaires

Question 59

It is the illumination where light received at the work plane or light illuminating an object is incident predominantly from a particular direction.

Answer 59

Directional lighting

Question 60

A luminaire that is designed to emit an intense, concentrated beam of light with usually no more than a 20° divergence (spread) from where it is directed.

Answer 60

Spotlight

Question 61

A luminaire that emits an intense light that is broader than a spotlight and that is capable of being pointed in any direction.

Answer 61

Floodlight

Question 62

A directional lighting installation where luminaires are attached to and are moveable along a metal track.

Answer 62

Track lighting

Question 63

A lighting installation in which the light on the working plane or on an object is not incident predominantly from a particular direction. Diffused light is cast and disbursed over a large area

Answer 63

Diffused Lighting

Question 64

A lighting installation where the light source is shielded by a panel that is parallel to the wall and attached to the ceiling.

Answer 64

Cornice Lighting

Question 65

A lighting installation where the light source is shielded by a panel that is parallel to the wall at the top of a window.

Answer 65

Valance Lighting

Question 66

It is the excessive brightness in the field of vision that causes discomfort or, in extreme cases, produces a disability from a temporary loss of vision.

Answer 66

Glare

Question 67

The most essential form of lighting because it is the basic background of light for almost every room

Answer 67

Ambient Lighting

Question 68

Lighting design that illuminates a specific visual function and can influence the effectiveness of the individual performing the task.

Answer 68

Task or local lighting

Question 69

Lighting design used to add drama and emphasize a particular object or area

Answer 69

Accent lighting

Question 70

Lighting design that aesthetically adds interest to the space by blending with other types of lighting to give an overall “feel” to a space.

Answer 70

Decorative Lighting

Question 71

The transitional space from public to private and exterior to interior.

Answer 71

Entrances

Question 72

Lighting should make the food, the table setting, and the people look attractive, so excellent color rendition is a must.

Answer 72

Dining spaces

Question 73

The best light washes the face from all directions, softening shadows

Answer 73

Restrooms/bathrooms

Question 74

Located in walls of a building, these are the most common method of introducing daylight into the interior building spaces.

Answer 74

Windows

Question 75

A transparent panel located in a roof opening that allows direct and diffuse sunlight into the building. A roof monitor is a type of skylight system that is a raised, typically triangular shaped, extension of a roof and that has at least one glazed surface.

Answer 75

Skylight