Question

How did the development of electrical signals sent through wires change communication?
• The electrical signals were more accurate than optical semaphore signals.
• Signals could be sent anywhere a wire could reach and no longer were restricted to line of sight.
• Signals were amplified with distance.
• Signals no longer attenuated with distance.

Answer 1

Answers:
- The first two statements are true.
- Electrical telegraphy was more accurate and reliable than optical semaphore: it worked in darkness and bad weather, reduced errors from mis-seeing flags, and could carry precise encoded messages.
- Because signals travel along a wire, messages could be sent wherever wires (or cables) ran rather than being limited to line of sight; submarine cables famously linked continents.
- The last two statements are false.
- Signals are not amplified by distance; they weaken (attenuate) as they travel. Early telegraph lines used relays or repeaters to regenerate the signal at intervals. Later technologies (vacuum-tube and transistor amplifiers) could boost signals, but the wire itself does not amplify with distance.