Answer: Question 1 (a)
Energy Energy Energy
Band gap Band gap
0 0 0
(i) Insulator (ii) Semiconductor (iii) Conductor
Diagram 1: The energy band
The differences between insulator, semiconductor and conductor.
Insulator Semiconductor Conductor
It has a large band gap. It has a smaller band gap. It has no band gap.
It has a higher resistivity. It has a moderate resistivity. It has a lower resistivity.
No movement of electron occurs, so the conduction band remains empty. It has enough energy to displace a few of …show more content…
Full-wave rectifier converts whole of AC cycle into pulsating DC while half-wave rectifier converts only one-half of AC cycle into pulsating DC. Moreover, the half-wave rectifier is unidirectional so, it only allows the conduction in one direction which means either it only can convert positive half or negative half into DC voltage while the full-wave is bi-directional so, it can convert positive half and negative half of the cycle into DC voltage.
Two networks that perform full-wave rectification are bridge network and center-tapped transformer.
For the bridge network, it has four diodes in bridge configuration. During the period 0 ≤t<T/2, D_2 and D_3 are conducting, while D_1 and D_4 are in the ‘off’ state. It results the positive region to the graph. During the period T/2≤t<T, D_1 and D_4 are conducting while D_2 and D_3 are in the ‘off’ state. It results the negative region to the graph. Bridge network has been used widely these days. It is more efficient used to transformer and does not required a center-tapped transformer. Graph 1: Full-wave bridge rectifier (Boylestad R.L, 2011) Sketch 1 (by Multisim): Full-wave bridge rectifier
Answer: Question 2
Energy Energy Energy
Band gap Band gap
0 0 0
(i) Insulator (ii) Semiconductor (iii) Conductor
Diagram 1: The energy band
The differences between insulator, semiconductor and conductor.
Insulator Semiconductor Conductor
It has a large band gap. It has a smaller band gap. It has no band gap.
It has a higher resistivity. It has a moderate resistivity. It has a lower resistivity.
No movement of electron occurs, so the conduction band remains empty. It has enough energy to displace a few of …show more content…
Full-wave rectifier converts whole of AC cycle into pulsating DC while half-wave rectifier converts only one-half of AC cycle into pulsating DC. Moreover, the half-wave rectifier is unidirectional so, it only allows the conduction in one direction which means either it only can convert positive half or negative half into DC voltage while the full-wave is bi-directional so, it can convert positive half and negative half of the cycle into DC voltage.
Two networks that perform full-wave rectification are bridge network and center-tapped transformer.
For the bridge network, it has four diodes in bridge configuration. During the period 0 ≤t<T/2, D_2 and D_3 are conducting, while D_1 and D_4 are in the ‘off’ state. It results the positive region to the graph. During the period T/2≤t<T, D_1 and D_4 are conducting while D_2 and D_3 are in the ‘off’ state. It results the negative region to the graph. Bridge network has been used widely these days. It is more efficient used to transformer and does not required a center-tapped transformer. Graph 1: Full-wave bridge rectifier (Boylestad R.L, 2011) Sketch 1 (by Multisim): Full-wave bridge rectifier
Answer: Question 2