Please solve this question ASAP.
Question 2
a) "Both dynamic and condenser microphones have a diaphragm that vibrates in accordance with the air movement around it, also known as the sound pressure level. The microphones then transform this diaphragm movement from acoustical energy into electrical energy. Despite the same transducer function, the working principles between these two transducers are different. A dynamic microphone can be categorized as an inductive transducer, whereas the condenser microphone represents a form of capacitive transducer."
Figure Q2(a) and Q2(b) illustrate schematic diagrams of both dynamic and condenser microphones. Explain the working principles of both transducers in greater detail. Based on appropriate diagrams, derive mathematical models for both transducers and abbreviate all variables used clearly. Assume that the sound pressure level causes the diaphragms to move by xm. (6 marks)
Magnet Diaphragm Coil
Diaphragm Back-Plate Case
+ve
+ve
Sound
Sound
-ve
-ve
n1
(a)
(b)
Dynamic Microphone Figure Q2(a) and Q2(b)
Condenser Microphone
b) A capacitive displacement sensor is used to measure a rotating valve, as shown in Figure Q2(c). The capacity is 800 pF with a round surface. Determine the change in capacitance for an oval surface (3 marks).
1 mm (oval surface)
5 mm (round surface)
Shaft
Shaft
Figure Q2(c)