AREN FINAL

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The general color rendering index (CRI) is an average of how many color shifts?

8

The three primary colors of light are

red, green, blue

Which photoreceptors connect to the non-image forming parts of the brain?

ipRGCs

Ultrasonic occupancy sensors can detect smaller motions than PIR sensors.

True

Ultrasonic occupancy sensors detect motion by sensing a shift in frequency of the ultrasonic waves that reflect to the sensor.

True

The rod photoreceptors are primarily located in which part of the retina?

Pheriphery

The mercury vapor in a fluorescent lamp produces mostly IR radiation when energized.

False

The term "brightness" means the same thing as the term "luminance."

False

The term "control zone" refers to a group of luminaires that perform the same task and are controlled in unison.

True

The term "vacancy sensor" refers to an occupancy sensor that automatically turns lights on whenever someone enters a space.

False

According to Flynn, impressions of spaciousness can be reinforced by uniform lighting that emphasizes perimeter architectural surfaces.

True

High pressure sodium lamps are known for producing a very warm color tone of light.

True

Suppose that you wanted to produce an illuminance of 200 footcandles on a statue, from a light source that is mounted 10 feet from the statue. What value of luminous intensity do you need coming from the light source in the direction of the statue?

20,000 cd

In general, people prefer colors that are more saturated than they appear under the reference light source.

True

An office is 15 ft by 15 ft with two luminaires, each of which has lamps producing 6000 lumens. If the CU value for the luminaires is 75% for the desktops, what is the estimated average illuminance on the desktops? (Rounded to the nearest whole number.)

40 fc

A light source has luminous intensity of 1000 candlepower at the center of its beam, and is mounted five feet above a table. The estimated illuminance on the table directly beneath the light source is:

40 lux

For the same luminaire used in #9 (6000 lumens output), the CU value for a 20' by 30' room is 0.80. How many luminaires would you need in this larger room to achieve an average illuminance of 64 fc?

8

A snowy morning, haze at twilight, and the diffuse light from the fabric structure at DIA are all examples of

Ambient Luminescence

In the IES TM-30 system, the R(f) metric has a range of values from 0 to 100.

True

Radiant power coming from a light source has units of

Additive

Lighting controls for daylighting can save energy in buildings by switching or dimming the electric lighting in areas where daylight is present.

True

A light source or luminaire typically has a single value representing its luminous intensity (candlepower).

False

A luminance contrast ratio of about 2:1 is needed to create a dominant focal point in a space.

False

Kelvin is a unit of which color metric?

CCT

The factor that expresses the percentage of the total light source lumens that reach the defined work plane is the

Coefficient of utilization

The reflectance values of room surfaces directly affect this value.

Coefficient of utilization

A red object looks red because it absorbs longer wavelengths of light in the "red" region.

False

According to Flynn, impressions of privacy can be reinforced by bright lighting that emphasizes central architectural surfaces.

False

Dimming systems in buildings provide convenience and aesthetics without changing the energy used by lighting.

False

Which of the following is not one of the Flynn lighting modes?

Daylight: Windows / No windows

In the IES TM-30 system, the R(g) metric has a range of values from 0 to 100.

False

Passive infrared (PIR) occupancy sensors broadcast IR waves into a room.

False

The National Electrical Code (NEC) states that a lighting circuit can carry 100% of the rated power (Watts) of the luminaires.

False

Which of the following best describes how a fluorescent light source creates light?

Electricity energizes low pressure mercury vapor which in turn energizes a phosphor

Which of the following best describes how an LED light source creates light?

Electricity flows across a P-N junction

The bending of light as it is transmitted through glass is known as absorptance.

False

One of the IES TM-30 color rendering metrics measures how well a set of test colors under a light source match their appearance under a reference light source. This type of color metric is a measure of:

Fidelity

When you are looking at a small object, at which part of the renting is the image being focused?

Fovea

One of the IES TM-30 color rendering metrics measures how the color saturation of a set of test colors shifts compared to their appearance under a reference light source. This type of color metric is a measure of:

Gamut

If test colors under a light source appear to be more saturated than under the reference light source, the R(g) metric is

Greater than 100

Which of the following is not a gaseous discharge lamp type?

Halogen

Which of the following lamp types does not require a ballast to operate?

Incandescent

This calculation method accounts for direct light only.

Inverse square cosine law method

This calculation method is used to estimate the illuminance at a specific point

Inverse square cosine law method

Calculating the illuminance at a point uses which of the following calculation methods?

Inverse square law method

Which of the following is not one of the forms of light play defined by Richard Kelly

Layers of light

The accumulation of dirt on a luminaire directly affects this value.

Light loss factors (LLF)

Most fluorescent and LED light sources currently available shift colors to be less saturated than they appear under the reference light source.

True

When you are in a very dark room, which photoreceptors are helping you see?

Rods

The height and proportions of a room are used to calculate this value.

Room cavity ratio (RCR)

Passive infrared (PIR) occupancy sensors require a direct line of sight to the motion being detected to work properly.

True

The lumen output of the luminaire directly affects this value.

None of the above

Christmas tree lights, crystal chandeliers, and a sparkling water feature are all examples of

Play of brilliants

Color preferences seem to be mostly affected by the saturation level of which hues?

Red

Patterns of luminance can reinforce wayfinding in architectural spaces

True

My kitchen has a polished hardwood floor. Light reflected from this surface is an example of what type of reflection?

Semi-specular

A lobby has a wall insert of highly polished chrome. Light reflected from this surface is an example of what type of reflection?

Specular

When a light source is pointed straight down, photometric measurement techniques consider the 0 degree angle to be in which direction?

Straight down beneath the light source

The phosphor coating on a fluorescent lamp absorbs UV energy and produces visible light.

True

The reference light source used for establishing color rendering metrics is called the blackbody radiator.

True

A dual technology occupancy sensor combines both passive infrared and ultrasonic sensing technology.

True

A light source or luminaire typically has a single value representing its luminous power

True

Elective power going into a light source has units of

Watts

Calculating the average illuminance in a room uses which of the following calculation methods?

Zonal cavity method

This calculation method accounts for both direct and inter-reflected light

Zonal cavity method

This calculation method is used to estimate the average illuminance on a work plane.

Zonal cavity method

Converting the output from a light source from radiant power to luminous flux involves what mathematical process?

applying the human visual response function


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