SNC2D Physics Test #1 Flashcards
What is light?
It is any kind of Electromagnetic Wave caused by vibrating atoms or electrons.
What is an Electromagnetic Wave?
They are light and are caused by vibrating atoms or electrons.
What is the visible spectrum?
It is the narrow range of light which is visible to the human eye.
What is incandescence?
It is heating things up like a flame or light bulb.
What is Fluorescence?
It is exciting atoms with one form of energy causing them to immediately produce another – tube lights.
What is Phosphorescence?
It is exciting atoms with one form of energy causing them to slowly produce another – ‘glow in the dark’
What is Chemiluminescence?
It is production of a light because of a cold chemical reaction (not burning) – glow sticks – in living things this is called Bioluminescence.
What is Electroluminescence?
It is produced when electrons fall into orbitals of atoms in LED semiconductors.
For an object to be Luminous means that…
The object produces its own light.
If an object is non-luminous it means that…
The object just reflects light, doesn’t give it off.
What is the speed of light and what is its symbol?
Its speed is 3.0 x 105 km/s (about 300 000 kilometers per second). It is such an important speed that it is given its own letter as a symbol c.
What does Rectilinear Propagation mean?
It means that light only travels in straight lines - as long as nothing gets in its way, that is.
What does the acronym SALT stand for? What do these things describe?
Size
Attitude
Location (position)
Type
These four things describe the way that light behaves.
What is a real image?
It is an image which can be projected on a screen.
What is a virtual image?
This is a image that appears only in the interacting surface (e.g. the mirror).
Define what size refers to (in reference to describing images with SALT).
Is the image the same size, larger or smaller than the original object?
Define attitude/orientation.
Define location/position.
The image may appear the same distance, nearer or farther away from the interacting surface than the original object. (“Objects in the rear view mirror are closer than they appear.”)
What are the two types of images?
Real and virtual.
What are the three types of mirrors? Explain each.
- Spherical - If the curve was extended it would form a ball.
- Parabolic - the curve was extended, the ends would never meet.
- Random - like a funhouse mirror.
What is a ray?
It is just a vector (line with an arrow) that shows the direction something is travelling.
What does the Law of Reflection state?
This law states that the Angle of Incidence equals the Angle of Reflection.
What is the normal line?
This is a line drawn perpendicular (at right angles) to the reflecting surface at the point where the reflection takes place. The angles of incidence and reflection are measured against it.
Define transparent.
This means that light can pass through an object.
Define translucent.
This means that light can pass through and object but lose intensity.
Define opaque.
This means that light cannot pass through the object.