Illumination

What is the frequency of flicker of a fluorescent lamp on a 60 Hz supply?

Which one is the working principle for high pressure mercury vapor lamp?

Which lamp has the highest power factor?

What is the purpose of the capacitor used in the autotransformer circuit for sodium vapor lamps?

What is the primary purpose of the choke in a fluorescent lamp?

Which of the following light source gives the highest lumen/watt?

Argon gas is used in a neon lamp to produce what color?

All of the following are the advantages of a tungsten filament lamp over the fluorescent lamp. Which one is not correct?

The heat from the filament of a lamp is transmitted to the surroundings through which of the following heat transfer principles?

Which law states that the illumination is directly proportional to the cosine of the angle made by the normal to the illuminated surface with the direction of the incident flux?

For the same lumen output, the operating cost of the fluorescent lamp is ____ that of a filament lamp.

Filament lamps normally operate at what power factor?

The luminous intensity of the lamp is expressed in which of the following units?

The illumination coming from the moonlight is about how much?

The output of tungsten filament lamp depends on which of the following?

What is the SI unit of illuminance?

Which of the following lamp has minimum initial cost of installation but maximum running cost?

The direct lighting system is most efficient but is liable to cause which of the following?

Which of the following lamps requires a cooling period prior to restarting?

In a fluorescent tube, a ballast resistance is connected in series with the choke under which of the following conditions?