"Telephone" Electromagnetic Wave PPT Courseware

Description

"Telephone" Electromagnetic Wave PPT Courseware

learning target

Understand the basic differences between analog and digital communications.

Learn how telephones carry sounds far away.

How telephones transmit information to distant places and the purpose of telephone exchanges.

Analysis of typical examples

[Example] Among the following parts, the one installed in the microphone is _________, and the one installed in the earpiece is___________.

A. Permanent magnet b. Solenoid C. Carbon particles D. Vibrating membrane made of carbon E. Carbon disc F. Vibrating membrane made of iron.

[Analysis] (1) The microphone has a vibrating diaphragm and carbon particles that beat with the sound. When people speak into the microphone, the diaphragm vibrates with the pitch of the sound, thereby compressing the carbon particles and converting the sound into In order to change the current signal, the components in the microphone include carbon particles, a diaphragm made of carbon, and a carbon disc. (2) There are electromagnets and diaphragms in the earpiece. When electrical signals of different strengths and weaknesses from the other party are transmitted to the earpiece, the electromagnet turns the electrical signals into vibrations of the diaphragm and restores the transmitted sound. Therefore, the components in the earpiece have Permanent magnets, solenoids, vibrating membranes made of iron. 【Answer】C, D, E; A, B, F.

Compliance test

1. Regarding carbon particle telephones, which of the following statements is correct ( )

A. The earpiece is filled with carbon particles B. The microphone is equipped with an electromagnet

C. The electromagnet in the earpiece works by utilizing the magnetic effect of current D. The current in the electromagnet is a stable current

2. Which of the following statements is correct ( )

A. The earpiece converts acoustic information into electrical signals B. The microphone converts electrical signals into acoustic signals

C. The inside of the earpiece uses electromagnets to work D. The microphone works using the principle of electromagnets

3. After the two phones A and B are connected, which of the following statements is correct ()

A. A's receiver and A's microphone, B's receiver and B's microphone are connected in series in two circuits.

B． A's receiver is connected in series with B's receiver, A's microphone is connected in series with B's microphone

C. A's receiver and B's receiver and microphone are connected in series in a circuit

D． A's receiver and B's microphone are connected in series in one circuit, and B's receiver and A's microphone are connected in series in another circuit.

4. Which statement about the telephone exchange is correct ( )

A. The emergence of telephone switches has greatly improved the utilization rate of telephone lines

B． When making a call, if a "busy" message appears, it must be because the other party's phone is in use.

C. Early telephone exchanges relied on operators to manually connect and disconnect lines, which was inefficient.

D． Modern program-controlled telephone exchanges utilize electromagnetic relays for wiring

5. Which of the following descriptions about analog signals and digital signals is correct ()

A. Digital signals may cause sound and image distortion when transmitted over long distances or amplified multiple times.

B． The analog signal form is simple and has strong anti-interference ability.

C. Digital signals can be encrypted with different encodings

D． Digital signals can be easily processed by electronic computers, thus giving full play to the huge capabilities of computers

Keywords: electromagnetic wave teaching courseware, telephone teaching courseware, Lujiao version ninth grade physics PPT courseware download, second volume, ninth grade physics slide courseware download, electromagnetic wave PPT courseware download, telephone PPT courseware download, .PPT format;

For more information about the "Electromagnetic Wave Telephone" PPT courseware, please click the "Electromagnetic Wave ppt Telephone ppt" tab.

30 PPT materials of white three-dimensional little people holding phones and making calls:

These are 30 PPT materials of white three-dimensional little people holding a phone and making calls. .PPTX format;..

"Telegraph and Telephone" Information Transmission PPT Courseware 2:

"Telegraph and Telephone" Information Transmission PPT Courseware 2 How to quickly transmit long-distance information? After three years of study by the American painter Morse, the first telegraph machine came out in 1837. Morse successfully replaced human civilization with the on, off and long interruption of electric current.

"Telegraph and Telephone" Information Transmission PPT Courseware:

"Telegraph and Telephone" Information Transmission PPT Courseware What is a telegraph? After three years of study by the American painter Morse, the first telegraph machine came out in 1837. Morse successfully used the on, off and long breaks of electric current to replace human words for transmission. This is Ding Ding..

File Info

Update Time: 2024-07-07

This template belongs to Physics courseware Lu Jiao Edition Ninth Grade Physics Volume 2 industry PPT template

Preview