1. Sundials:

2. What is a Sundial?
• A Sundial is a common
instrument used to tell the time.
As you can see in the name the
instrument uses the sun. They
show the time by a shadow of a
pointer casted by the sun onto a
flat surface indicating the
hours of the day on it.

3. How does a Sundial
Work?
• A Sundial works by a gnomon which is an essence on any
form of stick. The gnomon casts the shadow and determines
the solar time at that moment.
• As you can see by the name, a sundial is a instrument that
measures the time using the sun. As the sun moves across the
sky so does the gnomon, it moves towards the different hours
at the speed of the sun. Every design of a Sundial relies on the
gnomon, without the gnomon the sundial won’t be able to
progressively move from hour to hour.

4. How does a
Sundial Work?

5. Who uses Sundials?
Sundials are used all over the world,
therefore the first evidence of a Sundial
existing was in the Roman, Greek,
Babylonian and Egyptian
civilisations . They were known to be the
most accurate time readers in those
hotter areas of the world, so people
tended to use them more that other
clocks. The oldest sundial was
apparently developed in Greece in
around 340BC, so the Sundial was made
and used by a lot of people in that time
frame.

6. Summary
• A Sundial is a common instrument used to tell the
time. A Sundial works by a gnomon which is an
essence on any form of stick. The gnomon casts the
shadow and determines the solar time at that
moment. They are found all over the world.

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10. Summary: