Page 113 - Viva ICSE Science 5 : E-book
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• Note the position of the globe.
• Now rotate or spin the globe in a direction opposite to
the direction of the hands of a clock (anticlockwise).
You will see that the side of the globe facing the torch is in
the light (day time), whereas the other side is in the darkness
(night time). Here torch acts as the sun. As you spin the
globe, the dark side emerges towards the light and thus,
experiences the day.
In the same way, the rotation of earth on its axis causes the formation of day and night.
Eclipse
An eclipse is the partial or total blocking of the light of the sun by a heavenly body like
the earth or the moon. We already know that the earth revolves around the sun. Similarly,
the moon revolves around the earth. At times, all three of them come in a straight line.
In such a situation, the light of the sun is blocked by the body in the middle. Thus, it
casts its shadow on the third body. The third body is said to be eclipsed or hidden from
the sun. Depending on the third body which gets eclipsed by the shadow of the middle
heavenly body, eclipse is categorised into two types—solar eclipse and lunar eclipse.
Solar eclipse
When the sun, the moon and the earth are in a straight
Did You Know!
line in the same order, then the moon blocks the sunlight
Looking at the solar
reaching the earth and casts its shadow on the earth. This eclipse without eclipse
is called a solar eclipse. When the moon completely hides glasses or with the naked
eyes may cause harm to
the sun, it is a total solar eclipse. When it hides the sun only
your eyes.
partially, it is a partial solar eclipse. A solar eclipse lasts for
only a few minutes.
earth
moon
sun
partial solar eclipse
total solar eclipse
Solar eclipse
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