Electric Lighting

Which of these have a better efficacy?

• LED

• Incandescent

• Metal Halide

• Mercury Vapour

Efficacy is the ratio of?

• lux/watt

• lumen/watt

• intensity/watt

• %

Typical application of a low pressure sodium is

What lamp is used for indoor grows and stadiums?

Luminous intensity is measured in?

• Lumens

• Lux

• 
  Candela

If a light emits 1500cd and is 4m away from the surface, what is the total surface illuminance? (measured in lux)

If a light emits 2500cd at a distance of 3.5m from the surface, what is the total surface illuminance? (measured in lux)

What is the luminous intensity of a lighting emitting 250lux on a surface 3m away?

• 2000cd

• 2000lumens

• 2250lumens

• 2250cd

What is the average illuminance of a 10 x 10 room which has 12 lights rated at 10,000 lumens where the UF is 0.8 and MF is 0.9? (measured in lux)

What type of lamp is considered discharge lighting?

• Incandescent

• Metal Halide

• LED

• Mercury Vapour