Question: Does the halogen bulp increase, reduce, or have no effect on filament evaporation?
Answer: reduces

Question: How does the halogen bulb decrease darkening over time?
Answer: by redepositing tungsten from the inside of the bulb back onto the filament

Question: Does a halogen bulb operate at a higher or lower temperature than an incandescent?
Answer: higher

Question: How does the size of a halogen bulb compare to an incandescent?
Answer: bulbs are much smaller than normal incandescent bulbs

Question: What is the most common situation when a halogen bulb is used?
Answer: where intense illumination is needed in a limited space

Question: What did an alternate version of the incandescent lamp substitute for a wire filament?
Answer: an arc struck on a spherical bead electrode

Question: What was a common application for this type of bulb?
Answer: scientific instruments such as microscopes

Question: When was this style of lamp developed?
Answer: 1915

Question: What displaced this style of lamp?
Answer: mercury and xenon arc lamps

Question: What does a power factor of 1 mean?
Answer: the actual power consumed (in watts) and the apparent power (in volt-amperes) are equal

Question: What principally determines the wattage of an incandescent bulb?
Answer: the resistance of the filament

Question: What determines the resistance of the filament?
Answer: the filament's length, thickness, and material

Question: How close do incandescent lamps come to pure resistive loads?
Answer: Incandescent lamps are nearly pure resistive loads

Question: All other things being equal, how does wattage affect light emitted?
Answer: the higher-powered bulb gives more light

Question: What determines the resistance of a filament?
Answer: temperature

Question: What does a "T" rating symbol on an electrical contact mean?
Answer: they are designed to control circuits with the high inrush current characteristic of tungsten lamps

Question: How long does it take a typical 100-watt bulb to achieve 90% of its brightness?
Answer: 0.13 seconds

Question: How does the cold resistance of tungsten filament lamps compare to the hot resistance?
Answer: The cold resistance of tungsten-filament lamps is about 1/15 the hot-filament resistance

Question: What is the resistance of a typical lit 100-watt incandescent bulb?
Answer: 144 ohms

Question: What do the letters identify in a bulb shape designation?
Answer: the shape of the bulb

Question: What do the numbers identify in a bulb shape designation?
Answer: the maximum diameter

Question: Can the name of a certain bulb shape vary?
Answer: The names of the shapes may be slightly different in some regions

Question: What units are the bulb sizes measured in?
Answer: 1⁄8 of an inch, or in millimeters

Question: Which company introduced standard base sizes for incandescent lamps?
Answer: General Electric

Question: In what year were standard base sizes introduced for incandescent lamps?
Answer: 1909

Question: What are some common technical standards for lamp bases?
Answer: ANSI standard C81.67 and IEC standard 60061-1

Question: What is the typical base type for automotive lamps?
Answer: Bayonet base lamps

Question: What is the typical base type for halogen lamps?
Answer: bipin base

Question: What level of voltage reduction is required to double the life of an incandescent bulb?
Answer: a 5% reduction in operating voltage

Question: When did light bulb manufacturers establish a cartel to limit bulb life?
Answer: 1924

Question: When did authorities break up the light bulb cartel?
Answer: 1953

Question: What was the artificially low limit on bulb life placed by the cartel?
Answer: 1000 hours

Question: What is an example of a good application for a long-life bulb?
Answer: difficult-to-access location (for example, traffic lights or fixtures hung from high ceilings)

Question: When did the "Centennial Light" begin burning?
Answer: 1901

Question: How much light does the bulb emit?
Answer: the equivalent light of a four watt bulb

Question: When did the long-lasting bulb in Texas begin continuing illumination?
Answer: 21 September 1908

Question: Where did the Texas bulb begin its life?
Answer: an opera house

Question: At what temperature does a typical 50-hour-life projection bulb operate?
Answer: 50 °C (122 °F)

Question: Which metal has the highest melting point?
Answer: Tungsten

Question: What is the typical life of a P1 lamp?
Answer: as short as two hours

Question: How does the color temperature differ for photographic lighting?
Answer: higher color temperature

Question: How many lumens per watt does a typical 100-watt, 120-volt lamp produce?
Answer: 17.1 lumens per watt

Question: How many lumens per watt does a typical train light produce?
Answer: as much as 19.8 lumens per watt

Question: How does filament size relate to voltage level?
Answer: Lower voltage lamps have a thicker filament

Question: What is the effect of a thicker filament on bulb temperature?
Answer: They can run hotter for the same lifetime before the filament evaporates.

Question: What made power distribution economically viable in Edison's lamp?
Answer: high resistance

Question: How many inventors came up with electric lamps before Thomas Edison?
Answer: 22

Question: How did Edison achieve a higher vacuum than other inventors?
Answer: by use of the Sprengel pump

Question: Which historians wrote about the advantages of Edison's lamp over other early versions?
Answer: Robert Friedel and Paul Israel

Question: What can clothing provide during hazardous activities?
Answer: safety

Question: What type of surfaces can clothing protect from?
Answer: rough

Question: What does clothing keep toxic materials away from?
Answer: body

Question: What can insulate against cold or hot conditions?
Answer: Clothes

Question: What type of radiation can clothing provide some protection from?
Answer: UV

Question: What isn't it easy to determine about clothing?
Answer: when clothing was first developed

Question: What organism has provided some information about the timeline of clothing?
Answer: lice

Question: What habitat is the body louse specific to?
Answer: clothing

Question: What may modern humans be the only survivor of several species of?
Answer: primates

Question: How many thousands of years ago may have clothing been worn?
Answer: 650

Question: What obvious improvement does clothing bestow upon the wearer?
Answer: comfort

Question: In what type of climate does clothing protect against sunburn and wind damage?
Answer: hot

Question: What property of clothing is important in cold climates?
Answer: thermal insulation

Question: What has seasonal and regional aspects?
Answer: clothing

Question: What type of material tends to be worn in warmer seasons?
Answer: thinner

Question: What variety has there been in the materials of clothing throughout history?
Answer: very wide

Question: What is an article that is carried rather than worn that isn't regarded as clothing?
Answer: purses

Question: Jewelry isn't considered clothing because it's usually worn purely for what reason?
Answer: adornment

Question: What are footwear and hats both considered?
Answer: accessories

Question: What is an example of something that serves a function other than protection?
Answer: eyeglasses

Question: What does clothing protect from things which may injure it?
Answer: the uncovered human body

Question: Rain, snow, and wind are what class of things clothing protects the wearer from?
Answer: elements

Question: Clothing that is too sheer will offer less what?
Answer: protection

Question: What type of hazard is noxious chemicals?
Answer: environmental

Question: What type of clothing do doctors wear to protect their surroundings?
Answer: medical scrubs

Question: What animal has shown extreme inventiveness in the clothing it has devised?
Answer: Humans

Question: What are space suits an example of a solution to? 
Answer: environmental hazards