Optics Flashcards
Radio Waves
What are radio waves?
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light.
True or False: Radio waves can travel through a vacuum.
True
Which frequency range do radio waves typically occupy?
Radio waves typically occupy the frequency range from 3 kHz to 300 GHz.
Fill in the blank: The speed of radio waves in a vacuum is approximately _______ meters per second.
300,000,000
What is the primary use of radio waves?
The primary use of radio waves is for communication, including broadcasting and wireless networking.
What type of modulation is commonly used in AM radio broadcasting?
Amplitude Modulation (AM)
What type of modulation is commonly used in FM radio broadcasting?
Frequency Modulation (FM)
True or False: Radio waves can be reflected by surfaces.
True
What is the name of the phenomenon when radio waves bend around obstacles?
Diffraction
Multiple Choice: Which of the following is NOT a characteristic of radio waves?
A) They can be polarized
B) They travel at the speed of light
C) They require a medium to propagate
D) They can be reflected
C) They require a medium to propagate
What is the role of antennas in radio wave transmission?
Antennas convert electrical energy into radio waves and vice versa.
What is the term for the range of frequencies that a radio wave occupies?
Spectrum
Fill in the blank: The _______ band is commonly used for FM radio broadcasting.
VHF
What is the unit of measurement for frequency?
Hertz (Hz)
True or False: Longer wavelengths correspond to lower frequencies in radio waves.
True
What is the effect of distance on radio wave strength?
Radio wave strength diminishes with distance due to spreading and absorption.
Multiple Choice: Which of the following applications does NOT use radio waves?
A) Wi-Fi
B) Bluetooth
C) Optical fiber communication
D) Satellite communication
C) Optical fiber communication
What is the relationship between wavelength and frequency in radio waves?
Wavelength and frequency are inversely related; as frequency increases, wavelength decreases.
Fill in the blank: The _______ band is used for amateur radio operations.
HF
What is the purpose of a radio receiver?
A radio receiver converts radio waves back into electrical signals for audio output.
True or False: Radio waves can penetrate through buildings and other obstacles.
True
What is the Doppler effect in relation to radio waves?
The Doppler effect refers to the change in frequency or wavelength of radio waves due to the relative motion between the source and observer.
What is a common frequency for AM radio broadcasting?
Typically between 530 kHz and 1700 kHz.
What is the significance of the ionosphere for radio waves?
The ionosphere reflects certain radio waves, allowing them to travel long distances.
