Book 13, Question 111
Why Does a Flashlight Beam Get Wider the Farther It Goes?
A flashlight beam gets wider the farther it goes because light spreads out! The same light covers a bigger and bigger circle. So the beam gets weaker too.
More fun facts
- A flashlight beam is not perfectly straight; it spreads out from the bulb in a cone.
- The angle of the cone is called the opening angle.
- The farther the light goes, the wider the cone gets.
- Weather radar beams spread too, about 300 meters for every 16 kilometers they travel.
- At about 190 kilometers from the radar, its beam is over 3 kilometers wide.
Questions kids ask
Why does a laser spread less than a flashlight?
Laser light stays focused, while a flashlight beam spreads in a cone.