Spotlight Revision Practice Test

Measuring how far you can see in the atmosphere is visibility. A visibility meter is designed to quantify that distance by evaluating how much light from a target remains detectable over a known path, often using the amount of transmitted or scattered light. The reading reflects how fog, haze, rain, or smoke limit sight, giving a numerical value in units like meters or miles.

The other instruments measure different atmospheric properties: an anemometer tracks wind speed, a barometer measures atmospheric pressure, and a thermometer records temperature. While those factors can influence how conditions affect visibility, they don’t directly measure the distance you can see, so they aren’t used to gauge visibility.