Signals Beyond Speech

Question 1 · multiple choice

A lighthouse's repeated flash pattern helps identify…

Which light it is The sea's taste Tomorrow's fish catch The exact age of every ship

Question 2 · multiple choice

Semaphore sends messages chiefly with…

Flavours Paint drying Flag positions Ground vibrations only

Question 3 · multiple choice

An emergency siren uses a distinctive pattern chiefly to…

Measure wind direction Attract attention and signal urgency Cool the street Provide a concert

Question 4 · multiple choice

Why do railway signals need standard meanings?

Colours change train mass Different drivers must interpret them consistently Every train has the same length Signals remove braking distance

Question 5 · multiple choice

A QR code can still scan with some damage because it contains…

Indestructible ink Error-correction information A tiny battery Hidden radio transmitters

Question 6 · true false

True or false: A signal must be audible to carry information.

True False

Question 7 · multiple choice

A barcode scanner distinguishes patterns of…

Printing smell Paper thickness only Package weight only Contrasting bars and spaces

Question 8 · multiple choice

A radio receiver tuned to one station mainly selects…

The nearest printed logo Only the loudest human voice The oldest transmitter A particular frequency band

Question 9 · multiple choice

A message sent twice can reveal disagreement after a transmission error, but why may correction still be uncertain?

The shorter copy must be correct Repeating removes every error Two different copies do not identify the correct one Two copies must always match

Question 10 · multiple choice

A flashing light repeats every four seconds. One flash is missed. Why is a timing pattern still useful?

Later flashes can re-establish recognition The missed flash remains visible Timing removes fog Every light has that pattern