Sending Warning Signals

How did people send and receive warning signals very long ago? Alert on their phones Mail letters Using of their senses like hearing and sight Sending a telegram How were the towers along the Great Wall of China used in sending warning signals long ago? Archers would fire arrows from tower to tower Towers would blast music They would shake Smoke signals from fires What improved sending warning signals in the 1800s? electricity fast horses planes trains Which communication device uses Morse code to send information? telephone typewriter email telegraph Which are two disadvantages of using the telegraph to send warnings? cost to build and maintenance being able to read Morse code and message had to be sent directly through a wire message had to be sent directly through a wire and size of machine there were no disadvantages True or False? Telegraph messages were sent directly from sender to receiver? True False After a message is received by a telegraph station, which is a disadvantage for this type of communication? The message moved too slow through the wire. The person that the message was sent to could live miles away from the telegraph station. Only robots could read Morse Code Telegraph messages were too bright. Which technology allowed people to communicate with their voice instead of using Morse code? email voicemail telephone microphones After the telephone, which device also allowed people to send warnings over long distances using their voices? WiFi Telegram Radio Transmitter What is one disadvantage of sending warnings via radio? Radios have to be turned on in order to receive the warning Radios need batteries Only wealthy people have radios They only work over short distances What is a degraded radio signal? It is cheaper than others The signal bounces off the clouds The signal is in Morse code The signal becomes weaker as it travels longer distances What is the advantage of sending a signal in a digital format instead of analog? Digital signals are cheaper Digital signals can travel farther distances Analog signals are in Morse code More people have analog receivers Today, _ allow(s) us to warn thousands of people at once in the language that they prefer. electricity apps and push notifications loudspeakers cables Which method(s) of sending warning signals for a tsunami would most likely reach the most people? phone app alert loudspeaker telegraph message app alert and loudspeaker Sort the information Communication using voices telephone loudspeaker Communication without using voices telegraph mail service Which form of communication uses long and short taps? Norse Code Telephone Signals Morse Code texting Which device converts the sound of the person’s voice into an electrical signal that can be transmitted along a wire? telegraph microphone speaker