Light & shadows

Understanding light sources, how shadows form, and the properties of transparent, translucent and opaque materials

Name:

Date:

Try each question. If you're stuck, leave it and come back. The answer key is on the last page.

1
True or false? The Moon is a light source. A) True B) False
Answer:
2
Which of these is a light source? A) A candle flame B) A mirror C) The Moon D) A white wall
Answer:
3
Complete the sentence about how shadows form. A shadow forms when an object ___ light from passing through.
Answer:
4
Which type of material lets all light pass through it clearly? A) Transparent B) Translucent C) Opaque D) Reflective
Answer:
5
True or false? Light travels in straight lines. A) True B) False
Answer:
6
If you move an object closer to a light source, what happens to its shadow? A) The shadow gets bigger B) The shadow gets smaller C) The shadow disappears D) The shadow does not change
Answer:
7
Describe what translucent means. A translucent material lets ___ light through, so you can see shapes but not clear details.
Answer:
8
During the day, your shadow is shortest at midday. Why? A) Because the Sun is highest in the sky and light shines almost straight down B) Because you are taller at midday C) Because the Sun is furthest away at midday D) Because the ground is hotter at midday
Answer:
9
Explain why we cannot see in complete darkness. We need light to see because our eyes detect light that ___ off objects.
Answer:
10
True or false? A shadow is always the same size as the object that makes it. A) True B) False
Answer:

Answer key

Light & shadows · for parents and teachers

1
False
False. The Moon is not a light source - it reflects light from the Sun. A light source produces its own light, like the Sun, a torch, or a candle.
2
A candle flame
A candle flame produces its own light, making it a light source. Mirrors, the Moon, and walls only reflect light from other sources.
3
blocks
Shadows form when an opaque object blocks light. The dark area behind the object is where light cannot reach.
4
Transparent
Transparent materials (like clear glass) let all light through. Translucent materials let some light through (frosted glass). Opaque materials block all light (wood, metal).
5
True
True. Light always travels in straight lines. This is why shadows have sharp edges and why you cannot see around corners.
6
The shadow gets bigger
Moving an object closer to a light source makes its shadow larger because the object blocks a wider spread of light rays.
7
some
Translucent materials let some light through but scatter it, so you see blurred shapes. Examples include frosted glass and thin fabric.
8
Because the Sun is highest in the sky and light shines almost straight down
At midday the Sun is at its highest point, so light hits you almost straight from above, creating a short shadow directly below you. In the morning or evening, the Sun is low, casting long shadows.
9
reflects
We see objects because light reflects (bounces) off them and enters our eyes. In complete darkness there is no light to reflect, so we cannot see anything.
10
False
False. A shadow's size depends on the distance between the object and the light source. Closer to the light makes a bigger shadow; further away makes a smaller shadow.