T10L2 Flashcards
What did Samuel Morse invent?
Samuel Morse invented the electrical telegraph in 1837, and by the Civil War 1861, there were telegraph lines that carried Morse code across the country.
What is the difference between analog and digital signals?
Analog signals allows for a continuous record of some kind of action. They have the highest amount of resolution because of the continuous recording, but they take up a lot of space. Digital signals allows for a record of numerical values of an action at a set of continuous time intervals. They are stored as a series of numbers and can be easily saved and edited, but there is no record in between intervals.
What signal is continuous and which is discrete?
Analog = continuous
Digital = discrete
What is the difference between electronic and electromagnetic signals?
An electric signal is information that is sent as a pattern in a controlled flow of current through a circuit. The telegraph turns the current on and off to send a message, but it is very slow. Electromagnetic signals is information sent as patterns of electromagnetic waves such as visible light, infrared waves, microwaves, and radio waves. They do not need a circuit because they are wireless, making them travel at the speed of light.
Between electronic and electromagnetic signals, which is fastest, flexible, and wired?
Electronic = wired
Electromagnetic = fastest and flexible
What form of energy do electronic signals travel?
wave pulses
Which frequency do phones use?
Ultra - high frequency (UHF)
Which frequency do submarines use?
Extremely - low frequency (ELF)
How does sampling rate relate to the quality of a recording?
The higher the sampling rate, the richer and more detailed the file/sound becomes.
What are disadvantages of digital recordings?
You do not have any recording of any signals that happened in between sampling.
How would you define sampling rate?
How often a signal is recorded or converted to a digital code.
What is a byte?
The basic unit of a computer’s storage capacity.
What are real life examples of electromagnetic signals you use everyday?
light bulbs, microwaves, phones
How does a computer convert sound waves into binary code and back to sound waves again?
It will convert the sound waves into digital data known as binary code. The data is transmitted as microwaves, which converts to sound waves.
What are pixels and how does the amount of them affect quality of an image?
Pixels are small uniform shapes that are combined to make a larger image. The more pixels that are used, the higher resolution.
