Shadows
Click on the picture to do an interactive about shadows
If the light sources is distant, like the sun, the light comes in parallel rays and makes sharp shadows. If you have a small light source, like a very small flashlight, the penumbra is relatively small. If you have a large light source, the rays are coming at the object from a wider area, which creates a larger penumbra.
Watch the YouTube video below to see what happens with the moon and shadows.
Watch the YouTube video below to see what happens with the moon and shadows.
Learning about shadows
When an opaque object is placed in the pathway of a beam of light, a shadow is made.
1. A shadow is the area behind the opaque object where light is blocked
2. The closer an object is to the light source, the larger the shadow, because it is blocking more light
3. The darkest part of the shadow where the light is completely blocked, is called the umbra
a. The umbra is not absolutely dark because scattered light makes its way into the shadow
4. The fuzzy part of the shadow between the umbra and the light is called the penumbra
a.The penumbra occurs because…
i. The light source sends out light from different points and/or
ii. The light bends (act of diffraction) around the edge of the opaque object
1. A shadow is the area behind the opaque object where light is blocked
2. The closer an object is to the light source, the larger the shadow, because it is blocking more light
3. The darkest part of the shadow where the light is completely blocked, is called the umbra
a. The umbra is not absolutely dark because scattered light makes its way into the shadow
4. The fuzzy part of the shadow between the umbra and the light is called the penumbra
a.The penumbra occurs because…
i. The light source sends out light from different points and/or
ii. The light bends (act of diffraction) around the edge of the opaque object