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### Course: Middle school physics - NGSS>Unit 4

Lesson 6: Digital signals

# Digital signals

Review your understanding of digital signals in this free article aligned to NGSS standards.

## Key points:

• Information can be stored in digital or analog form. Digital information is made from a certain set of values, or digits. Analog information is made from possibilities within a range.
• For example, a digital clock can show time with the exact values $0$-$9$. But the hands on an analog clock can point to any value in the range from $0$-$12$.
• Information in waves can be transmitted with either digital or analog signals using wave properties like frequency or amplitude.
• The properties of a digital signal match specific values, or digits in their set of values.
• The properties of an analog signal can be any value within a range.
• Digital signals are more reliable because interference or noise can be easily removed from the received signal. However, every change within an analog signal contains some information, so interference or noise can be almost impossible to remove.

## Want to join the conversation?

• I would like to know that what course should I take for physics subject after finished this middle school physics, please?
• High School Physics
OR
High School Physics - NGSS
• "Digital signals are more reliable because interference or noise can be easily removed from the received signal. However, every change within an analog signal contains some information, so interference or noise can be almost impossible to remove." do you mean that interference can be removed from digital but not from analog?
• Essentially. Digital values are exact, they leave little room for interpretation, but Analog has more room for error, but also, more room for interpretation. Depending on what Analog is being used for, this could be a good thing.
• *MY first comment omg*
• What is the bad side of Digital analogue?
• I would probably say deletion and theft
• I have no Questions
• this is very hard
• i found it out now
• If waves have ups and downs depending on its volume, it can be that the starting of the wave is at 2, but it doesn't end at two, then how do you find its wavelength if you need to look at its identical points?
• The wavelength of a wave is the distance between two identical points in the wave. To find the wavelength of a wave, you can use the equation: wavelength = speed of the wave / frequency of the wave. The speed of the wave is usually given in meters per second (m/s) and the frequency is given in hertz (Hz).12

So if you know the speed and frequency of a wave, you can easily calculate its wavelength using this equation. I hope that helps!
• what a fun lesson!
• which clock would be the better option to use ?
• i think its analog