ALE Building Utilities (Acoustics and Lighting

Sound

"Is a physical wave, a mechanical vibration, a series of pressure variations, in an elastic medium

20 to 20000 HZ

A healthy pair of human ear has a detection range of.

344 m/ sec.

Sound travels in air, at sea level, in ____ m/sec.

Frequency

"The number of times the cycle of compression and rarefaction of air makes in a given unit of time.

Reverberation

"Is the persistence of sound after the cause of sound has stopped-a result of repeated reflections.

Echo

"Is caused when reflected sound at sufficient intensity reaches a listener approximately 70 m/ sec. after hear the direct sound.

Flutter

"Is perceived as a buzzing or clicking sound, and it is comprised of repeated echoes traversing back and forth between two non-absorbing parallel surfaces.

Fibrous Materials

A device used for sound absorption

Creep

This describe the reflection of sound along a curved surface near the surface

344 m/sec

Sound travels only about ___________m/sec.

decibel

It is the measurement of the intensity of sound.

40 db

It is the limit for comfortable hearing.

Reverberation time

"It is the time in seconds that a reflected sound diminishes for the case by 60db after the original sound has stopped."

omnidirectional mic

"It is a type of microphone which equally sensitive sound arriving at it from any direction"

incandescent

"It has a stimulating effect, conducive to drinking, induces sleep, best for bars and night club."

photometry

"In theory and fundamentals of lighting. It is the science that deals with measurement of light."

candle power

"It refers to the unit of intensity of light of one standard candle whose light is concentrated at a point and the light source is assumed to be placed at the center of a hollow sphere of one foot radius."

Diffusion

"In physical principles of light, it is the light rays leaving the source strike through, opaque surface which spreads the light in various directions, in addition light is broken up while in reflection, the light bounces back at a different direction."

Lumen

"It is the unit of luminous flux, amount f light falling on a surface from the source."

the reciprocal of ohm

"Mho as used in electrical systems calculation is defined as _______."

Watt

"A unit of mechanical power is horsepower. What is electrical power?"

1 lumen per sq.m.

"In lighting and illumination calculation, what is the unit for lux?"

Varies inversely with

"In Inverse Square Law, it states that: “sound intensity ______ the square of the distance from the source.”"

Decibel

"Is a logarithmic unit of measurement that expresses the magnitude of a physical quantity (usually power or intensity) relative to a specified or implied reference level."

droppler effect

"An apparent shift in the frequency occurring when an acoustic source and listener are in motion relative to each other, the frequency increasing when the source and the listener approach each other and decreasing when they move apart"

flutter

What is a repetitious reflective sound due to parallel walls?

Echo

– delayed sound heard a fraction of a second after the direction of sound isheard

Noise

unpleasant or unwanted sound

psycho acoustics

What is the study of reactions of humans to audible sound?

environmental acoustics

study of effects on environment upon audible sound

electro acoustics

study of sound generated by equipment

wavelength

What is the distance between two similar points in succession waves traveling in one cycle?

frequency

rate of repetition of a periodic phenomenon

sound

"a sensation felt by the brain resulting from the distance of molecules in the air"

magnitude

What is the amount of sound energy produced by the source?

decibel

unit of loudness of sound

velocity

at speed of sound normal temperature and pressure

sound foci

What is the reflected sound that gathers in a central portion of the room?

dead room

one characterized by large amounts of absorption

Live room

characterized by very small amounts of absorption

reverberation

What is the persistence of sound after the source of sound has stopped?

resonance

state existing in a system which is set into oscillation

pure tone

"simplest kind of sound composed entirely of sound waves of a single frequency"

Specific Lighting

"A type of lighting that provides illumination to special objects like sculptures, flower arrangements, etc."

Phon

Unit of loudness level.

Sound Absorption

"The process of dissipating sound energy by converting it to heat."

Wavelength

Distance sound travels during each cycle of vibration.

Sound Attenuation

"The reduction in the intensity or in the sound pressure level of sound which is transmitted from one point to another."

Sabin

"Unit of sound absorption equivalent to 1 square foot of perfectly absorptive material."

Sound Diffraction

"Acoustical phenomenon which causes sound wave to be bent or scattered around"

Threshold of Audibility

"Minimum sound pressure level that is capable of being detected by the human ear"

Sound

"Fluctuation in pressure, a particle displacement in an elastic medium."

Pure Tone

Sound sensation in a single frequency.

Sine Wave

Wave produced by a pure tone.

Luminaire

Synonymous with a lighting fixture.

Candela

The luminous intensity of light is expressed in ___.

General Lighting

"Type of lighting dealing with relatively large area lighting."

Luminous Flux

The rate of flow of light through a surface.

Luminance

"The luminous intensity of any surface in a given direction per unit of projected area."

Foot-Candle

"A unit of illumination equivalent to 1 lumen per square foot."

Lux

"A unit of illumination equivalent to 1 lumen per square meter"

Indirect Lighting

"Type of lighting system where 90-100% of light output is directed to the ceiling and upper walls of the room"

Cathode

The equivalent of filament in a fluorescent lamp.

Sound Intensity

The rate of flow of sound energy

Accent Lighting

"Lighting used primarily to draw attention to particular points of interest."

Fluorescense

A means of producing light from gaseous discharge.

High-Pressure-Sodium

A type of High-Intensity-Discharge lamp (HID).

Microphone

"Sound system input device that reacts to and converts variable sound pressure into variable electrical current."

Cross Light

"Light originating from sources not facing each other, as from windows in adjacent walls."

Luminaire

A lighting unit consisting of one or more electrical lamps.

Eggcrate

"A louvered construction divided into cell-like areas and used for redirecting the light emitted by an overhead source."

Floodlight

"A lamp designed to project and diffuse a uniform level of illumination over a large area."

Passive Infrared

"A type of perimeter detector which detects object in heat range of body temperature."

Passive Infrared

"A type of perimeter detector which detects interruption of light beam."

Ultrasonic

"A type of perimeter detector which detects change in sound wave pattern."

Microwave

"A type of perimeter detector which is subject to false alarm from aircraft radar and from movement outside building through window, wood doors, and the like. It uses radio waves."

Passive Infrared with Ultrasonic (or Microwave)

"This type of perimeter detector uses both the Passive infrared and Ultrasonic or Microwave system."

Proximity / Capacitance

"This type of perimeter detector detects a change in capacitance of the area covered, caused by intrusion. Proximity / Capacitance a. Microwave"

Metal Halide Lamp

"A high intensity discharge lamp in which the light is produced by the radiation from a mixture of a metallic vapor, similar to that of a mercury lamp in construction."

Mercury Lamp

"A type of lamp popular for lighting commercial interiors, uses argon gas to ease starting, it produces light by means of an electric discharge in mercury vapor."

Tungsten Halogen Lamp

"A type of lamp which produces light by means of the reaction of halogen additive in the bulb reacts with chemically with tungsten."

High-Pressure-Sodium (HPS)

"A type of lamp generally used for roadways and sidewalks, uses sodium gas."

Frequency

"The number of cycles per unit time of a wave or oscillations expressed in hertz of cycles per second."

Transmission Loss

"Of a partition, the number of decibels by which sound is reduced in transmission through it; a measure of the sound insulation value of the partition, the higher the number, the greater the insulation value."

Infra Red

"212. The other type of flame detector other than the ultraviolet type."

Porous Absorbents

"What type of sound absorbent is best for lower band frequencies."

Refraction

"The bending of sound wave when traveling forward changes direction as it passes through different densities."

1 lumen per sq.m.

In lighting and illumination calculation, what is the unit for lux?

Magnetic flux

Tesla is the unit of____.

Varies inversely with

"In Inverse Square Law, it states that: “sound intensity ______ the square of the distance from the source.”"

Curve surface

Creep is the phenomenon whereby sound travels in a ______.

All of the above

"Sound Transmission Loss (STL) is/are affected by the following ____.

a. Intensity of sound from source

b. Material density

c. Medium

All of the above

"Which of the following factors affect/s room acoustics?

a. Shape and proportion of room

b. Room cavity

c. Seating and other furnishings

Nadir

"A condition characterized as vertically downward directly below the luminaire. What is that term?"

Sound absorption

"It is the product of surface area (sq.ft.) and sound absorption coefficient (SAC). It has the unit sabin."

Architectural acoustics

"Wallace Clement Sabine, an American physicist who pioneered work on sound is said to be the father of ____?"

Structureborne sound

"When sound impinges on a surface such as walls, floor, ceiling, etc. It is referred to as _____."

Environmental acoustics

"A branch of acoustics that involves the control of noise pollution, environmental noise, which include motor vehicles, aircraft noise, etc."

Hermholtz resonator

"This material is so named in honor of a German physicist, consist a of a holllow material with a small hole on one side. This is used to detect individual frequency of complex acoustic wave configuration."

Individual resonator

"A type of resonator made from empty clay vessels of different sizes. Their absorption ranges from 100-400 hertz."