علوم الصف الخامس المنهج الجديد لغات

المدير العام علم بلدك :

Unit
1 : Energy Lesson 1 : light

Light :

A form of energy that affects eye
causing the sense of seeing (vision )

Difference
between light energy and other forms of energy :

Lightenergy differ than other kinds of energy

Because :

It is visible energy .

Sources of light
:

1. The Sun :

The main source of light on earth's
surface

2. The moon :

Moon's light is a reflection of sunlight
that falls on its surface .

Visible Spectrum
:

Light energy which can be seen by the
eye

Travel
of light

v Light
travels in straight lines .

Example :

The Straight line :

is The path

1.Which is taken by light rays coming
from the car torch .

2.Which is taken by beam of sun rays
coming from the sun and passes through a narrow hole of a window or a
dark room

Activity prove
that :

Light travels in straight lines

Tools : lighted candle – straight cylinder of length 50
cm

Steps :

1.Fix a lighted candle vertically

2.Put one of the 2 ends of the straight
cylinder

in front of the candle flame

3.Look at the flame of the candle .

Observation :

You can see the flame

4.Bend the cylinder (not straight )

5.Try to look at the candle flame
through the bent cylinder

Observation :

You can't see the flame.

Conclusion :

Light travels in straight lines

Activity prove that :

Light travels in
straight lines

Tools :lighted candle – 3 cardboard screens

Steps :

1.Bring 3 pieces of cardboard , each
containing a hole .

2.Put them in a row in front of a
lighted candle .

Where all holes and the flame are on one
straight line .

3.Look to the candle flame through the
hole of the last pieces of cardboard .

Observation :

You can see the flame

4.Move any of the pieces of the
cardboard to right or left

The 3 pieces are not on one straight line .

5.Try to see the candle flame through
the hole of the last pieces of cardboard .

Observation :

You can't see the flame .

Conclusion :

Light travels in straight lines

Phenomena happen
due to traveling the light in straight lines :

1.Formation of images through narrow
holes

2.Formation of shadows

Formation of
images through narrow holes :

When light travels through
narrow holes :

An inverted image is formed is formed

It leads to :

Designing of photographic camera .

Activity proves
that :

Light travels
through narrow holes forming An inverted image :

Steps :

1.Bring a cardboard ( metallic ) box
opened from on side .

2.Cover the open side by a
semi-transparent paper (white balloon )

3.Make a small hole on the opposite side
of the box.

In a dark room :

4.Move a lighted candle in front of the
small hole

of the cardboard box Until an inverted
is formed .

Observation
:

An inverted image for the candle is
formed

Conclusion :

Light travels through narrow holes in
straight lines forming An inverted image .

v This activity is the base of idea
of the camera

v This
box is called pin-hole camera

عضو VIP

[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]

الموضوع مكرر

[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]

[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذا الرابط]

[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]