At the same time the Egyptians invented the “shadow clock ‘, other cultures developed a need to organize their time better. Ma Chinese, Greeks and Romans developed another device for telling time known as the” Sundial “. Sundials not necessarily work better than shadow clocks; it’s just a slight change in shade clock. Make your own “Sundial” counting the time in this science experiment
What you need:
• thick cardboard
how to continue
1. stiff piece of cardboard, draw a right-angled triangle in the picture above. Shortly sides of the triangle should be about 150mm long, but long side will be 200mm, along the longitudinal axis angle used for the town. Make sure that you also add the base, below the dotted line.
2. Cut out the triangle, and make fold along the dotted line to form the basis for a triangle to stand.
3. Make a thick base for your sundial out of corrugated cardboard or wood of about 150x300mm in size. Draw a semicircle on the base as shown in the picture above.
4. Glue the folded portion of the triangle firmly at the base and set the sundial on a flat surface outside so that the triangle points north / south.
5. Mark the position of the shadow that falls on the bottom of the hour. Notice the shadow travels the same distance along a semicircle hourly. On a sunny day you will now be able to tell the time by looking at the position of the shadow on the sundial phone!
In the above science experiment that we have built up indicated device called “Sundial”. This works because the shadow change direction, time of day. The position of the sun in relation to a specific location on Earth changes throughout the day as the earth rotates around its own axis in 24 hours. A ‘Sundial’ like this, uses state of the shadows to tell time. Position sure semi-circle depends on the time of day, but it also depends on the season. It is the position of the sun at certain times of day is different in different seasons
More facts :.
The obvious problem with “sundials” and “shadow clocks” is that they do not work at night time! King of Egypt, was not happy having to check the position of the stars to know what the time is at night, as one of rulers made him a water clock. A water clock works by taking a large bucket of water, fill it with water up to a line and then cut a small hole in the bottom of the bucket, and meted out lines on the bucket after each hour had passed. The problem with the water clock is water flows more slowly or quickly when the temperature changes. The same principle was used but the water was replaced with sand to make sand clock. The inventor of the sand clock is unknown, but the sand clock or hourglass was commonly used in ancient times and is still used today.