Microphones, speakers, telephone receivers, and telephone microphones are all based on the principle of electromagnetic induction: sound vibrations cause resistance changes, current changes, and changing magnetic fields, thereby producing induced currents
Motors: energized coils are affected by the magnetic field. Ampere's force rotates and converts electrical energy into mechanical energy. It is not a phenomenon of electromagnetic induction.
Generator: A energized coil rotates in a magnetic field and generates an induced current. Converting mechanical energy into electrical energy is a phenomenon of electromagnetic induction.
Electricity Problems with magnetism
Question 1: The working principle of a dynamic microphone. It is made by utilizing the electromagnetic response phenomenon.
When sound waves vibrate the metal diaphragm, the coil (called the voice coil) connected to the diaphragm vibrates together, and the voice coil vibrates in the magnetic field of the permanent magnet. An induced current (electrical signal) is generated. The magnitude and direction of the induced current change. The changes in amplitude and frequency are determined by sound waves. This signal current is amplified by the amplifier and then transmitted to the speaker, and the amplified sound is emitted from the speaker.
Question 2: Are the principles of moving coil microphones and earphones the same? The microphone changes and the current generates a magnetic field. The earphone changes the magnetic field and generates an electric field. Because the sound drives the diaphragm to vibrate, the magnetic material of the earpiece is uneven. Changes in the magnetic field generate current
Question 3: The principle of moving-coil microphone Moving-coil microphone (moving-coil microphone) Engineering acoustics moving-coil microphone, moving coil Microphone) is a device that converts sound into electrical signals. Dynamic microphones are made using the phenomenon of electromagnetic induction. When sound waves vibrate a metal diaphragm, a coil (called a voice coil) connected to the diaphragm vibrates together, and the voice coil vibrates in the magnetic field of a permanent magnet. Among them An induced current (electrical signal) is generated. The magnitude and direction of the induced current change. The amplitude and frequency of the change are determined by the sound wave. This signal current is amplified by the amplifier and then transmitted to the speaker, and the amplified sound is emitted from the speaker.
Question 4: The working principle of the dynamic microphone in the picture is the same (C Analysis: Since the working principle of the dynamic microphone is electromagnetic induction, only the power generation in C The principle of the machine is the same, so choose C
Question 5: What are the principles of dynamic microphones and speakers? Generators and motors
Question 6: The working principle of dynamic microphones is the same as that of electrical appliances. The structure of dynamic microphones is the same as that of dynamic headphones! The working principle is the opposite! The former is that sound waves push the diaphragm! The coil on the membrane core vibrates in the strong magnetic gap! The latter is the coil generating an alternating magnetic field through the audio current! It interacts with the permanent magnet to cause the vibrating membrane to emit sound waves! Electromagnetic>: Features: Requires electricity
Electromagnetic crane, motor, speaker, electromagnetic relays, telephone receivers, and electric bells.
Generator, dynamic microphone