Light Energy

Light Energy

By Christine Tan 4E

Light Energy for Plants

The leaves of a plant use light from the Sun to make food.

Sources of Light at Night

The moon is often the brightest object in the night sky but is NOT a source of light.

Stars are sources of light that help us to see at night.

Why does the Moon Look Bright?

It looks bright because it reflects light from the Sun.

Path of Reflected Light

Light Eye/Screen

Mirror/Smooth Surface

Properties of Light

Light is a form of energy. Light enables us to see

things Light can be reflected off surfaces

Light travels in straight lines.

ShadowsThe property of light that explains why shadows are formed is : LIGHT TRAVELS IN STRAIGHT LINES.

Shadows can have different sizes as the objects causing them. But they have a similar shape.

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Distance between light source and object

Size of Shadow

Shadows and the Sun

Click here for a fun interactive activity (1)

The length of a shadow changes over the day due to the changing positions of the sun over the planet.

At noon the Sun is directly above the person so the shadow formed is the shortest.

Click here for a fun interactive activity (2)

Shape and Size of Shadow

The shape and size of shadows can be

changed by changing the distance between

the light source and the object.

Click here for a fun interactive activity (3)

SunglassesIdentify the property of sunglasses that make them useful for wearing on sunny days.

The lenses of the sunglasses are made of a material that allows only some light to pass through them.

It allows the wearer to see while keeping the glaring sunlight out of the eyes.