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Signals: Light and Sound Signals

Grade 1
Jun 7, 2023


Light helps us see different objects and their various colors through a process called reflection of light in which a part of it bounces off surfaces giving our eyes a view of its shape and the different colors associated with it. Also sound helps us communicate with each other through our voices, listening to music, etc.

Explanation of Signals:

Information can be communicated by various means. One of them being widely used is verbal communication. However, it is more convenient to use other modes of communication such as signals to convey certain information which is understandable by people of any language or dialect, or origin would understand. Such communications are done in two ways:

  1. Light signals
  2. Sound signals

Light Signals:

Lights on a traffic signal tell the drivers and pedestrians what to do.

The vehicles stop on seeing a red traffic signal. The pedestrians cross the road on seeing the same red signal. The communication was done with the car driver and the students via a red traffic signal.


However, the vehicles move on, seeing a green traffic signal. The pedestrians wait near the zebra crossing on seeing the same green signal. The communication was done with the car driver and the students via a green traffic signal.

Light signals

The blinkers of the car moving ahead tells a driver moving behind about the turn (left or right) it will take.


Sound Signals:

Vehicles on the road blow horns at each other. Blowing horn attracts attention from others. It would mean any of the following:

  • The driver wants your car to move.
  • The driver wants you to notice him/her.
Vehicles blowing horns

The police cars have flashing lights on top and a loud siren. These indicate that it is a police car and we should move out of the way. Light and sound can be used as signals.

light and sound signals of a police car

Questions and Answers:

  1. What does the light signal given below indicate?

The ambulances have flashing lights on top and a loud siren. These indicate that it is an ambulance carrying a patient and we should move out of the way.



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