2. • LIGHT TRAVELS IN A STRAIGHT LINE
KNOWN AS A RAY.
• LIGHT TRAVEL AT THE SPEED OF 300000 KM
/SEC.
• WHEN LIGHT STRIKES ANY OBJECT IT IS
REFLECTED.
3. THERE ARE MAINLY THREE TYPES OF OBJECTS.
THEY ARE
• OPAQUE OBJECTS
• TRANSLUCENT OBJECTS
• TRANSPARENT OBJECTS
4. A shadow is an area where direct light from a
light source cannot reach due to obstruction
by an object.
5.
6.
7.
8. • THE SIZE AND SHAPE OF SHADOE IS NOT ALWAYS SAME .THEY CAN
CHANGE IN SHAPE ;THEY CAN CHANGE IN SIZE.
• LARGER SOURCE OF LIGHT GENERATES UMBRA AND PENUMBRA
WHEREAS SMALLER SOURCES GENERATES SHADOW OF SHARP EDGES.
• LIGHT FROM SOURCE CAN BE OF HIGH INTENSITY AS WELL AS OF LOW
INTENSITY ACCORDINGLY SHADOW WILL ALSO GENERATES.
• WHEN LIGHT FALLS ON AN OBJECT A SHADOW CAN BE SEEN ON THE
SURFACE DIRECTLY BEHIND THE OBJECT .
• IF THE SURFACE US CLOSE TO THE OBJECT ,THE SHADOW IS THE SAME
SIZE OR LITTLE BIGGER THANTHE OBJECT ITSELF.IF THE SURFACE IS
FUTHER AWAY ,THE SHADOW APPEAR MUCH LARGER.
• SHADOW CAN GIVES US SOME IDEA OF TIME OF DAY.
9. • THE PARTIAL OR COMPLETE OBSCURING ,RELATIVE TO
DESIGNATED OBSERVER,OF ONE CELESTIAL BODY TO
ANOTHER.
• WHEN THE SUN ,THE MOON AND THE EARTH ARE DIRECTLY IN
LINE WITH EACH OTHER AN ECLIPSE TAKES PLACE.
• THERE ARE TWO KINDS OF ECLIPSES
1. SOLAR ECLIPSE
2. LUNAR ECLIPSE
10.
11. Solar
Eclipse
A SOLAR ECLIPSE OCCUR WHEN THE MOON COMES
BETWEEN THE SUN AND EARTH.THE MOON IS
OPAQUE,AND BLOCK OUT THE LIGHT OF SUN .SOME
TIMES ONLY A PART OF SUN IS BLOCKED OUT THIS
CALLED A PARTIAL ECLIPSE.SOME TIMES WHOLE OF
THE SUN LIGHT IS BLOCKED OUT;THIS TOTAL ECLIPSE.
12.
13.
14.
15. • A Lunar eclipse occurs when the Moon passes
directly behind the Earth into
its umbra (shadow). This can occur only when
the Sun, Earth, and Moon are aligned exactly,
or very closely so, with the Earth in the
middle.
