Light & Shadows Flashcards
(23 cards)
What is a source of light?
An object that gives out light.
Name 3 sources of light.
Sun, candle flame, torch.
Can we see objects that don’t give out light?
Yes, only when they reflect light into our eyes.
How does light travel?
In straight lines.
Why can’t we see around corners?
Because light doesn’t bend around corners.
What is reflection?
When light bounces off a surface into our eyes.
Name a material that reflects light well.
Mirror.
What do different materials reflect?
Different amounts of light.
What is light intensity?
How bright the light is in an area.
How do we measure light intensity?
Using a light sensor and data logger.
What happens to light intensity as you move away from the light source?
The light intensity decreases.
What causes a shadow?
An object blocking light.
Why can’t light go around the object?
Because it travels in straight lines.
What kind of materials form shadows?
Opaque materials.
What happens to the shadow when the object gets closer to the light source?
The shadow gets bigger.
What happens to the shadow when the object moves away from the light source?
The shadow gets smaller.
What affects the shadow’s shape and size?
The object’s shape, distance from the light, and angle of the light.
When is the Sun the highest in the sky?
Noon, 12pm.
When is a shadow the shortest?
When the Sun is directly above.
What did people use shadows for in the past?
To tell time with sundials.
Light sources __________ light.
Light sources <emit> light.</emit>
Size of shadow on a screen can be changed by changing the ______________ between light source and object.
Size of shadow on a screen can be changed by changing the <distance> between light source and object.</distance>
How can we see an object?
We see an object when light reflects off the object into our eyes.
