Lighting and power socket

In a filament bulb, the mixture of __________ gases allows the lamp to burn at higher temperature.

    

• Mercury and Nitrogen

• Argon and Nitrogen

• Sodium and Argon

• Argon and Mercury

In a Halogen Tungsten incandescent lamp, what is the function of Bromine and Iodine?

           

• It is to increase the brightness of the lamp.

• It is to reduce overheating.

• It is to limit the current supply.

• It is to assist the evaporated material back to the tungsten.

In a Vacuum type incandescent bulb, _______________ causes the lamp to blacken quickly.

.           

• rapid evaporation of filament due to lack of gas

• sudden increase of supply due to lack of gas

• rapid evaporation due to coiled-coil filaments

• none of the above

In discharge lamps, ballast is one of the most crucial lighting control gears. This is because __________.

     

•        ballast limits the current supply.

• ballast injects high current to start the lamp.

• ballast improves the power factor.

• ballast reduces the increasing temperature in the lamp.

To obtain the actual current flowing in a circuit feeding discharge lamps, the rated lamps wattage must be multiplied by a factor of __________ and divide the product with the rated voltage.

• 0.85

• 1.25

• 1.6

• 1.8

In a High Pressure Sodium vapor lamp, how much time does it take for the lamp to reach its full brightness?

        

• 5 minutes.

• 6 minutes.

• 15 minutes.

• Nearly instantaneous.

Preheat starting method consists of................(More than one correct answer)

• Glow type

• Thermal type

• Rapid starting

• Instant start

The symbol as shown in Figure stands for?

          

• Lamps served with internal ballast

• Lamps served with internal igniter

• Lamps served with capacitors

• Lamps requiring external igniter

In an instant start lighting system, the ballast __________ until the lamp reaches full brightness.                   

           

         

• injects high voltage and regulates the voltage into its normal operating value

•   injects normal operating voltage and gradually increases the voltage

• injects high current and regulates the current into its normal operating value

• injects normal operating current and gradually increases the current

The figure above shows a typical mercury vapour lamp. Which part is filled with a mixture of Mercury and Argon gases?

• A

• B

• C

• D