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WorksheetsElectromagnetic Waves and Modern Communication
Total questions: 27
Worksheet time: 24mins
Which of the following statements about electromagnetic waves and sound waves is incorrect?
Electromagnetic waves and sound waves can both propagate in a vacuum.
Electromagnetic waves and sound waves cannot propagate in a vacuum.
Which of the following statements about electromagnetic waves and sound waves is incorrect?
Electromagnetic waves and sound waves can both propagate in a vacuum
Electromagnetic waves and sound waves can both transmit information
Electromagnetic waves and sound waves both have energy
The sonar system uses ultrasound for positioning
Which of the following statements about various waves encountered in life is correct?
Electromagnetic waves can transmit information, sound waves cannot
Mobile phones involve both electromagnetic waves and sound waves
The propagation speed of sound waves and electromagnetic waves is the same
The infrared rays emitted by the remote control cannot propagate in a vacuum
Among the components of electromagnetic waves, which wavelength is used by the remote control of the television?
Gamma rays
Visible light
Infrared rays
Radio waves
Which of the following devices works using the information characteristics of electromagnetic waves?
Mobile phone
Disinfection cabinet
Microwave oven
Hair dryer
Given that the wavelength in a vacuum of electromagnetic waves is λ microwave > λ infrared > λ ultraviolet, what can be said about their frequencies?
f microwave = f infrared = f ultraviolet
f microwave > f infrared > f ultraviolet
f microwave < f infrared < f ultraviolet
f ultraviolet < f microwave < f infrared
In 1966, Chinese physicist Gao Kun proposed the idea of fiber optic communication. What is the carrier of information transmitted by fiber optic communication?
Electric current
Ultrasound
Radio waves
Light waves
Vehicles are often equipped with Global Positioning System (GPS) receivers to receive signals emitted by satellites for precise positioning and navigation. What is the medium through which satellites transmit information to GPS receivers?
Laser
Electromagnetic waves
Infrared rays
Ultraviolet rays
光纤通信传输信息的载体是什么？
无线电波
光波
卫星向GPS接收器传送信息通过的是？
激光
电磁波
红外线
紫外线
对电磁波的认识,下列说法错误的是？
可见光也是一种电磁波
红外线比紫外线的频率低
真空中不同电磁波的传播速度不同
电磁波的频率越高,波长越短
下列对电磁波的认识,正确的是？
电冰箱是利用电磁波工作的
可见光不属于电磁波
电磁波可以用来传播信息
电磁波在真空中的传播速度是3.0×105 m/s
下列说法正确的是？
电磁波和声波在空气中的传播速度都是3×102 km/s
电磁波和声波都是由物体振动产生的
手机无线上网是利用电磁波传递信息
电磁波能传递能量,声波不能传递能量
下列关于信息传递的说法,正确的是？
声、光和无线电波都能传递信息
无论何种信息的传递都需要介质
固定电话、移动电话、广播和电视都是利用导线中的电流传递信息
微波通信、卫星通信、光纤通信、有线网络通信都是利用电磁波传递信息
科学探测得到的图像和数据是通过什么传递到地球的？
声波
电磁波
把信息从月球传到地球的时间是？
(a)
The scientific detection images and data are transmitted to Earth through (fill in 'sound wave' or 'electromagnetic wave'). If the distance from the Moon to Earth is 3.8×10^5 km, then the time to transmit information from the Moon to Earth is _____ s (c=3×10^5 km/s, keep two decimal places).
sound wave
electromagnetic wave
The aircraft that can effectively avoid radar detection is called a 'stealth aircraft'. Its surface has a special material that can (fill in 'enhance' or 'weaken') the absorption of electromagnetic waves; its surface is made into a special shape, and the intensity of the electromagnetic waves emitted by the radar (fill in 'enhance' or 'weaken') when encountering the aircraft.
enhance
weaken
When unlocking the voice password lock of a mobile phone, only the person who set the voice password can say the password to unlock the phone. This voice password records the _____ characteristics of a person's voice; the mobile phone transmits information through _____.
timbre
electromagnetic wave
We live in an ocean of electromagnetic waves. When we need to prevent electromagnetic wave interference, we usually use a metal shell to isolate the electromagnetic waves from the area that needs to be shielded, avoiding the entry of electromagnetic waves. This practice is called electromagnetic shielding. The China Science and Technology Museum has a metal small house, and a piece of electromagnetic shielding glass is embedded in the large window on the side. Please design an experiment with selected materials to test whether this electromagnetic shielding glass can shield electromagnetic waves. Write out the experimental steps and judgment methods.
Read the short text and answer the questions. Geostationary Satellite. The launch process of artificial geostationary satellites can be simplified into two stages: ignition acceleration and attitude adjustment. From the ground, it appears to be stationary above the equator, synchronized with the Earth's rotation, hence the name geostationary satellite. Three communication satellites are deployed at an altitude of about 36,000 km above the equator to achieve global communication except for the poles. Geostationary satellites are commonly used in communication, meteorology, broadcasting, missile warning, data relay, etc., to achieve continuous work in the same area. (1) The synchronous satellite is _____ (fill in 'moving' or 'stationary') relative to the ground. (2) In the ignition acceleration stage, energy is converted from chemical energy → internal energy → _____ energy. (3) It takes at least _____ s for the electromagnetic wave signal sent from the ground to return through the synchronous satellite. (4) The uses of synchronous satellites include _____ (just name two).
The main use of optical fibers is to transmit information.
The main use of optical fibers is to transmit information, converting the information to light signals that propagate in the fiber. What is the propagation method of light in the fiber?
Straight line along the central axis of the fiber
Multiple refractions along the outer wall of the fiber
Multiple reflections along the inner wall of the fiber
Spiral curve along the fiber
The GPS positioning and navigation system in cars uses __________ (fill in 'ultrasonic' or 'electromagnetic wave') for positioning and navigation, and this wave __________ (fill in 'can' or 'cannot') propagate in a vacuum.
electromagnetic wave
can
The speed of electromagnetic waves in a vacuum is 3×10^8 __________ (fill in the unit); the longer the wavelength of electromagnetic waves, the __________ their frequency; electromagnetic waves __________ (fill in 'can' or 'cannot') propagate in a vacuum.
m/s
low
can
Mobile phones have become essential communication tools, transmitting information through __________. With the continuous development of mobile charging technology, advanced technologies such as wireless charging and solar charging are gradually entering our daily lives. The image above shows a real object of wireless charging for mobile phones. During the charging process, electrical energy is converted into __________ energy. The transformation or transfer of energy is __________, so the available energy sources are limited.
Electromagnetic waves have many family members, including radio waves, infrared rays, visible light, ultraviolet rays, X-rays, and gamma rays. The following statements about the application of electromagnetic waves are correct:
The banknote verifier uses infrared rays to identify the authenticity of banknotes
Mobile phones use radio waves to transmit signals
The remote control uses ultraviolet rays to control the TV
The microwave oven uses ultraviolet rays to heat food
