1).which of the following lamps is the cheapest for the same wattage.
a) Fluorescent tube.
b) Mercury vapour lamp.
c) GLS lamp.
d) sodium vapour lamp.
2).For the same lumen output,the running cost of the fluorescent lamp is.
a) equal to that of filament lamp.
b) less than that of filament lamp.
c) more than that of filament lamp.
d) any of the above.
3).For the same power output.
a) high voltage rated lamps will be more sturdy.
b) low voltage rated lamps will be more sturdy.
c) both low and high voltage rated lamps will be equally sturdy.
4).The cost of a fluorescent lamp is more than that of incandescent lamp because of which of the following factors.
a) More labour is required in its manufacturing.
b) Number of components used is more.
c) quantity of glass used is more.
d) All of the above lactors.
5).The function of capacitor across the supply to the fluorescent tube is primarily to.
a) stabilize the arc.
b) reduce the starting current.
c) improve the supply power factor.
d) reduce the noise.
6).A substance which change its electrical resistance when illuminated by light is called.
d) none of the above.
7).In electric discharge lamps light is produced by.
a) cathode ray emission.
b) ionisation in a gas or vapour.
c) heating effect of current.
d) magnetic effect of current.
8).In electric discharge lamps for stabilizing the arc.
a) a reactive choke is connected in series with the supply.
b) a condenser is connected in series to the supply.
c) a condenser is connected in parallel to the supply.
d) a variable resistor is connected in the circuit.
9).In an incandescent lamp bird cage filament is usually used in vacuum bulb so as to.
a) reduce the oxidation phenomenon.
b) reduce the convection losses.
c) have uniform radiations.
d) increase the life span of the filament.
10).stroboscopic effect due to use of discharge lamps in workshops results in moving machinery appearing.
b) stationary running slow.
c) stationary running in reverse direction.
d) all of the above.