gen-define-the-equation-of-time-and-give-one-short-worked-exampl-8ef4

Define the equation of time and give one short worked example.

# Equation of Time ## Definition The **equation of time** is the difference between apparent solar time (time shown by a sundial) and mean solar time (time shown by a clock). **Equation of Time = Apparent Solar Time - Mean Solar Time** It arises because: 1. Earth's orbit is elliptical (not circular), causing varying orbital speed 2. Earth's rotational axis is tilted relative to its orbital plane The equation of time varies throughout the year from about -14 minutes to +16 minutes. ## Worked Example **Problem:** On February 12, the equation of time is approximately -14 minutes. If a sundial reads 12:00 noon (apparent solar time), what time does a clock show (mean solar time)? **Solution:** Using: Equation of Time = Apparent Solar Time - Mean Solar Time -14 min = 12:00 - Mean Solar Time Mean Solar Time = 12:00 - (-14 min) Mean Solar Time = 12:00 + 14 min = **12:14 PM** **Answer:** The clock shows 12:14 PM when the sundial shows noon. This means the Sun is "running slow" — it crosses the meridian 14 minutes before clock noon.