EDC Quiz 3

The resistance of an LDR ______ when light intensity increases.

• Increases

• Decreases

• Remains constant

• First increases then decreases

Which material is commonly used in LDR construction?

• Silicon

• Germanium

• Cadmium Sulfide (CdS)

• Gallium Arsenide

The phenomenon responsible for light emission in LED is:

• Thermionic emission

• Electroluminescence

• Photoluminescence

• Field emission

Which characteristic is NOT typical of LASER light?

• Coherence

• Monochromaticity

• High divergence

• High intensity

A photodiode operates in:

• Forward bias only

• Reverse bias only

• Both forward and reverse bias

• Zero bias only

The current generated in a photodiode is proportional to:

• Applied voltage

• Temperature

• Light intensity

• Resistance

A phototransistor provides ______ compared to a photodiode.

• Lower sensitivity

• Higher current gain

• Faster response time

• Lower output current

In a BJT, the base region is:

• Heavily doped and thick

• Lightly doped and thin

• Heavily doped and thin

• Lightly doped and thick

For proper operation of NPN transistor in active region:

• Both junctions forward biased

• Both junctions reverse biased

• Base-emitter forward biased, base-collector reverse biased

• Base-emitter reverse biased, base-collector forward biased

In Common Base (CB) configuration, the input is applied between:

• Base and collector

• Emitter and base

• Emitter and collector

• Base and ground