Advertisements
Advertisements
प्रश्न
When an electric field is applied across a semiconductor ______.
- electrons move from lower energy level to higher energy level in the conduction band.
- electrons move from higher energy level to lower energy level in the conduction band.
- holes in the valence band move from higher energy level to lower energy level.
- holes in the valence band move from lower energy level to higher energy level.
विकल्प
a and b
b and c
d and a
a and c
उत्तर
a and c
Explanation:
In the valence band electrons are not capable of gaining energy from the external electric fields. While in the conduction band the electrons can gain energy from the external electric field.
When an electric field is applied across a semiconductor, the electrons in the conduction band (which is partially filled with electrons) get accelerated and acquire energy. They move from lower energy levels to higher energy levels. While the holes in the valence band move from higher energy level to lower energy level, where they will be having more energy.
APPEARS IN
संबंधित प्रश्न
(i) Explain with the help of a diagram the formation of depletion region and barrier potential in a pn junction.
What causes the setting up of high electric field even for small reverse bias voltage across the diode?
With reference to semiconductor devices, define a p-type semiconductor and a Zener diode.
Draw a labelled diagram of a full wave rectifier. Show how output voltage varies with time if the input voltage is a sinusoidal voltage.
The graph shown in the figure represents a plot of current versus voltage for a given semiconductor. Identify the region, if any, over which the semiconductor has a negative resistance.
The plate current in a diode is 20 mA when the plate voltage is 50 V or 60 V. What will be the current if the plate voltage is 70 V?
The dynamic plate resistance of a triode value is 10 kΩ. Find the change in the plate current if the plate voltage is changed from 200 V to 220 V.
In Figure, Vo is the potential barrier across a p-n junction, when no battery is connected across the junction ______.
In the depletion region of a diode ______.
- there are no mobile charges.
- equal number of holes and electrons exist, making the region neutral.
- recombination of holes and electrons has taken place.
- immobile charged ions exist.
Differentiate between the threshold voltage and the breakdown voltage for a diode.