Time Dilation in Daily Life, The GPS Connection
Introduction:
Relativity can sound like science fiction, but it quietly shows up in real technology. GPS satellites carry very accurate clocks. Because satellites move fast and are higher above Earth’s gravity than we are, their time does not match our time perfectly. Engineers correct those tiny differences so your phone can locate you accurately.
This activity helps students understand that even tiny time changes can matter when clocks must stay perfectly matched.
What You Will Need:
Two timers (two stopwatches, or two phone timers)
A ruler or measuring tape
Paper and pencil
Optional: a short hallway or open space
Step-by-Step Instructions:
Start two timers at the same moment. Label one “Earth clock” and one “satellite clock.”
Walk across the room slowly while holding the “satellite clock.” Keep the “Earth clock” on the table.
After one minute, stop both timers and compare. They will match, because we are not moving fast enough for real relativity effects.
Now do the important part: imagine the satellite clock is off by a tiny amount each day, even just a few microseconds.
Explain how a small time error could turn into a distance error if the system uses time to calculate position.
Write a short explanation: “If the clock is wrong, then the location will be wrong because…”
What to Look For:
Why do we use time to calculate distance in GPS systems?
Why does GPS require clocks that match extremely well?
How can a tiny error grow into a big problem?
Fun Fact:
GPS works by timing how long a signal takes to travel from a satellite to your device. The speed of the signal and the travel time together reveal distance.
Safety Tip:
Stay aware of surroundings when walking with a phone timer. Keep eyes up in hallways.
Journaling Prompt:
Write a paragraph explaining why Einstein’s ideas matter to something you use today. Choose GPS, phones, or space travel.