Why is the sky blue?
A simple question that reveals how sunlight behaves in the air around us.
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6 useful explanations to browse.
How does GPS know where you are?
Your phone estimates its location by listening to precise signals from satellites.
How do solar panels make electricity?
Sunlight can be converted directly into electrical power using semiconductor cells.
What causes earthquakes?
The ground can move suddenly when accumulated stress overcomes friction along a fault.
Why do we have leap years?
The seasons do not fit neatly into a calendar of exactly 365 whole days.
Why does the ocean rise and fall?
The changing pull of the Moon and Sun drives the repeating pattern of ocean tides.