All About Light
What is light?
Light is a form of electromagnetic energy that our eyes can detect. It travels in a straight path.
Light enters the eye through the _________.
Pupil.
What are some examples of transparent, translucent and opaque materials?
- Clear glass is transparent.
- Tissue paper and sunglasses are examples of translucent objects
- Examples include wood, a metal spoon, and a cardboard box.
What is matter?
Matter is anything that has mass (weight) and takes up space.
Melting and freezing occurs when...
Melting occurs when a solid becomes a liquid. Freezing occurs when a liquid becomes a solid.
What is the speed of light?
The speed of light is 300 000 km per second!
The _________ focuses light correctly on the retina.
Lens.
What is sound?
Sound is created when something vibrates and sends waves of energy or vibration into our ears.
What are the three main states of matter?
There are three main states of matter: Solid, liquid, and gas.
Puddles disappearing from the sidewalk during a hot summer day is an example of _________________.
Evaporation.
How does light travel? What are they called?
Light travels in straight paths called light waves.
The _________ is located at the back of the eyeball.
Retina.
What is the difference between sublimation and deposition?
Sublimation is when a solid turns to a gas without passing through the liquid stage. Deposition is when a gas turns to a solid without passing through the liquid stage.
What are the particle arrangements for solids, liquids and gases?
Solids have particles that are packed together very tightly. There is very little space between them. Liquids have particles that are packed together more loosely than solids, but more densely than gases. Gases have particles that are more spread apart than both solids and liquids. These particles move freely at high speeds.
__________ degrees represents the freezing point of water and ________ degrees represents the boiling point of water.
0 and 100.
What is the difference between absorption, reflection and refraction?
Absorption of light occurs when light stops at the object and does not reflect or refract. Reflection of light occurs when light bounces off the surface of a material. Refraction of light occurs when light passes through an object and bends.
Light can be absorbed, reflected (bounced off), and refracted (bent). What happens to the light depends on the surface it hits.
What does the optic nerve do?
The optic nerve receives light signals and sends a message to the brain to create images.
Water droplets that form on a window when warm air meets cooler air is an example of ____________.
Condensation.
What does physical property mean?
A physical property is any property that is evident without a chemical reaction.
What is thermal energy?
Thermal energy is the energy in an object due to the movement of its molecules and atoms.
What is the difference between natural and artificial light?
Natural light is light that is produced by things in nature, such as the Sun. Artificial light is light from things made by humans, usually powered by electricity or gas.
How do glasses protect or improve your vision?
Glasses bend light rays to focus light on the correct spot of your retina.
How is dry ice different from water ice? What is dry ice used for?
Dry ice is a solid form of carbon dioxide. It has a lower temperature than water ice, so it is usually used to keep things cool when refrigerators or freezers are not available. It can make smoke-like fog for haunted houses or events with special effects.
Snow thawing and creating puddles of water in the spring is an example of _______________.
Melting.
Why does frost form?
Frost forms when warm, moist air comes into contact with cold surfaces.