• 1. Shadows require light.
• 2. Light travels in a straight line.
It does not bend around an object.
• 3. An object has a shadow
because it affects light in some
way. It blocks or deflects light.
• 4. There are faint shadows and
strong shadows, depending on
how much an object blocks or
changes the light that passes
through the object.
• 5. The shape of a shadow
depends on the shape and
orientation of the object casting
• 6. We usually see shadows as
two-dimensional shapes on a
surface, but shadows also fill
• 7. Light interacts with matter.
• 8. Objects placed close to the
light source – shadow is big and
• 9. Objects placed close to the
screen – shadow is small and
• 10. A ball or sphere has the
same shadow no matter how you
change its orientation (position).
• 1. Light travels in straight lines.
When the light is blocked by an
object in its path, light cannot get
behind the object. That is why a
• 2. We can explain the shadows
we see by using diagrams. The
straight lines show some possible
paths that light can follow.
• 3. A narrow light source makes a
• 4. A wide light source makes a
• 5. If light from part of a source
reaches a certain place, that
place is not fully lit or fully
shaded; it is partially shaded.
• 6. An object that receives light
from more than one light source
can have more than one shadow.
• 1. We used a light beam to
observe how light interacts with
• 2. Saw light reflected, scattered,
transmitted and absorbed.
• 3. Observed three optical
properties of matter: transparent,
translucent and opaque.
• 4. A material can reflect the light
beam into one beam, a diffuse
glow or something in between.
• 5. A material can absorb the light
beam, completely or partially.
• 6. A material can transmit the
light beam largely unchanged.
(stays a beam)
• 7. A material can transmit light as
a diffuse glow.
• 1. Shadow size can be predicted.
• 2. Identifying variables and
making measurements are
important parts of the scientific
• 3. In an experimental system
there are independent and
• 4. Tables and graphs are ways to
• 5. Studying graphs helps us see
what the data means.