How to measure the height of a tree?

We can do this By Comparing Shadows

What do we need for this task?





We need to measure how long are the shadows
of the stick and our tree...

BC:CA=ED:DA

... to make proportions and to solve them

So, we have choosed our first tree, and measured the
shadow...

We have measured how long is the stick and his shadow...

...and made some calculations

We’ve measured the second one...

...and found the height...