Mcqs On Illumination | Objective Questions And Answers On Illumination | All Student World 1.4

Mcqs On illumination | Objective Questions And Answers On Illumination | All student world

1).which of the following is not the standard rating of GLS lamps?
a)    100 W.
b)    75 W.
c)    40 W.
d)    15 W.

2).colour of light depends upon
a)    frequency.
b)    wave length.
c)    both(a)and(b).
d)    speed of light.

3).what percentage of the input energy is radiated by filament lamps?
a)    2 to 5 percent.
b)    10 to 15 percent.
c)    25 to 30 percent.
d)    40 to 50 percent.

4). .....photometer is used for comparing the lights of different colours?
a)    Grease spot.
b)    Bunsen.
c)    Lummer brodhum.
d)    Guilds flicker.

5).the vapour discharge tube used for domestic lighting has
a)    no filament.
b)    one filament.
c)    two filaments.
d)    three filaments.

6).sky appears blue because of
a)    refraction.
b)    reflection.
c)    radiation.
d)    scattering of light over dust particles.

7).Fine diameter tungsten wires are made by
a)    turning.
b)    swaging.
c)    compressing.
d)    wire drawing.

8).Filament lamps operate normally at a power factor of
a)    0.5 lagging.
b)    0.8 lagging.
c)    unity.
d)    0.8 leading.

9).Most affected parameter of a filament lamp due to voltage change is
a)    wattage.
b)    life.
c)    luminous efficiency.
d)    light output.

10). a cold cathode lamp.
a)    Fluorescent lamp.
b)    Neon lamp.
c)    Mercury vapour lamp.
d)    Sodium vapour lamp.