Light Interactions
Light travels in what kind of path?
Straight Lines
When light bounces off a surface, what is this process called?
Reflection
What part of our body detects light?
Eyes
What happens when a warm object is placed near a cold one?
Heat flows from the warm object to the cool one.
Name one way heat can move.
Conduction, convection, or radiation
What is the difference between opaque and transparent?
Transparent lets light through
opaque blocks light
When light passes through a transparent material, we say it is ___
Why can’t we see objects in a completely dark room?
There is no light reflecting off them into our eyes.
Why does condensation form more on a metal cup than on a plastic or foam cup?
The metal cup gets colder faster because it conducts heat away from the air, causing more water vapor to cool and condense.
When water vapor in the air changes into liquid droplets on a cold cup, what process is happening?
Condensation — gas changing into a liquid as energy is released.
In the box + one-way mirror model, how does lighting on each side affect what you can see?
You see through from the darker side; the bright side mostly reflects.
When light hits an object and is absorbed, what happens to the energy?
It turns into heat (thermal energy).
Why do you see your reflection in a mirror but not in a wall?
Mirrors reflect light evenly; walls scatter it.
What happens to particles during evaporation?
Particles at the surface of a liquid gain enough energy to break away and become a gas.
Why does a paper cup or foam cup keep a drink warm longer than a metal cup?
Paper and foam are insulators, so they slow down the transfer of heat between the liquid and the surrounding air.
What causes shadows to form?
Light is blocked by an object.
How does the brightness on each side of a one-way mirror affect what you can see?
The brighter side reflects more; the darker side lets you see through.
How can ray diagrams help us understand light?
They show how light travels and reflects to reach our eyes.
Which heats faster, water or metal, under the same energy input — and why
Metal, because it has a lower specific heat capacity.
How can you tell that energy transfer is occurring when condensation appears on the outside of a cold cup?
The air around the cup cools, and water vapor loses energy, turning into liquid water droplets—evidence of heat transfer.
Why does a one-way mirror only “work” under certain lighting conditions?
It depends on having a bright side (high reflection) and dark side (low reflection) so light mainly goes one way.
Compare how light behaves in mirrors, windows, and translucent materials.
Mirrors reflect, windows transmit, translucent materials scatter light.
How do models help explain why we can see through some materials but not others?
Models show how light interacts differently with transparent, translucent, and opaque materials.
Why does adding energy make a thermometer’s liquid rise?
Particles move faster, spread out, and expand the liquid
Given a stack of metal, foam, and glass, which layer resists heat flow most?
Foam, because it traps air and reduces conduction.