How is television different from radio
A: Sound is changed into electromagnetic waves.
B: Light is changed into electromagnetic waves.
C: Both sound and light are changed into electromagnetic waves.
D: Either sound or light is changed into electromagnetic waves.
A: Sound is changed into electromagnetic waves.
B: Light is changed into electromagnetic waves.
C: Both sound and light are changed into electromagnetic waves.
D: Either sound or light is changed into electromagnetic waves.
举一反三
- When these electromagnetic waves escape from the conductor into space, they are said to be radiated by the conductor, hence the name radio waves.
- electromagnetic waves
- Electronic energy can be changed into light energy______ into sound energy. A: well B: as well C: too D: as well as
- Which is NOT the correct description about Laser? A: It stands for Light Amplification by Stimulated Emission. B: It’s a beam of light energy. C: All the light waves in a laser are emitted in the same rhythm. D: The light waves in a laser are of different wavelengths.
- Consider an interference between two waves. At a certain position if the vibrations caused by two waves are in phase, they make a destructive interference.? 正确|错误