Page 17 - Dream 2047 June 2020

ANNULAR S LAR ECLIPSE ACTIVITIES
Object
Diameter
Radius = Diameter/2
Sun’s image
S=
Moon’s image
M=
Object
Diameter
Distance between mirror projector and projected image
Sun’s image
S=
=L
Moon’s image
M=
Calculation for finding the percentage of Annular Solar Eclipse
For finding the percentage of Annular Solar Eclipse, the following formulation can be used:
Percentage of Annular Solar Eclipse (P)= Area of Moon’s image x100 => πM2 x100
Finding the angular size of Sun:
By using small angle formula, the angularsize of Sun can be calculated as,
Ө = 360° s s 2π L
Finding the angular size of Moon:
By using small angle formula, the angular size of Moon can be calculated as,
Ө =360°M M 2π L
ACTIVITY-4
Observing Nature during the Solar Eclipse
Place of observation: Duration of observation:
For conducting this activity, you need to take this observation sheet with you and need to go in the nature. You consistently need to observe nature and try to answer the following questions.
Observing sea waves
• Start observing sea waves and sea water level at the coastline a day before the eclipse. Note down the observation of sea waves and sea level after every hour. Write down your observation and comments.
Plant behaviour
• Did you find any plant which behaves abnormally during the eclipse period? If yes, can you note down your observations. (Hint: Try to look at the leaves and flowers of plants which require sunlight!)
Animal behaviour
• Did you find any animal which behaves abnormally during the eclipse period? If yes, can you write the names of the animals and their abnormalities?
Bird behaviour
• Did you find any bird which behaves abnormally during the eclipse period? If yes, can you write the names of the birds and their abnormalities?
Dr B.K. Tyagi is Scientist ‘F’ in Vigyan Prasar. Email: bktyagi@vigyanprasar.gov.in Translation: Ram Sharan Das
Area of Sun’s image
=> P=M2x100 S2
πS2
ACTIVITY-3
Finding Angular size of Sun and Moon
Projection of Sun
With the help of a coordinator or team leader, make the arrangement of projecting the Sun as shown in the picture in Activity -1
At the instant when you get the projected image of Sun as shown above, you are supposed to draw the Sun’s and Moon’s image on the screen either using pencil or a marker. In addition to this, you need to measure the distance between the mirror projector and the projected image of the Sun as shown above.
Observation Table
From projected images of the Sun and Moon you are supposed to measure the diameter of Sun’s and Moon’s image and fill the table below:
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