Physics chapter 13 Flashcards
What is the speed of light?
300,000km/s
How do we see things?
When light is reflected off of the item and into or eyes
What is a luminous object?
An object that produces light
What is a non-luminous object?
An object that reflects light
Properties of light?
. Travel in a straight line
. Travels faster than sound
. We see things when light is reflected into out eyes
. Shadows are created when an object blocks the light
What are the two laws of reflection?
- Incident ray, reflected ray, and the normal to the reflecting surface lie on the same plane
- The angle of incidence and the angle of reflection are equal
Define virtual image?
A copy of an object formed at the location from which light rays appear to come
Define real image?
The image which is formed when the light rays meet at a particular point after reflection from the mirror
What is the main difference between real and virtual image?
The real image can be obtained on the screen whereas the virtual image cannot be obtained on the screen.
Properties of images formed in a plane mirror?
. The same size as the object
. The same distance behind the mirror as the object in front of it
. Left and right are inverted
. Virtual
Define ray diagram?
A diagram showing the path of rays of light
Define sharp real image?
An image that can be displayed on the screen
How is a sharp real image formed?
When all rays from one point on an object arrive at a unique point of the image
Define refraction of light?
The bending of light as it passes from one transparent substance to another
In which direction does light refract when moving from a low density substance to a higher-density substance (Air to Water)?
It would reflect towards normal
In which direction would light refract when moving from a high-density substance to a low density (Water to Air)?
It would move away from normal
The formula for refractive index (n)?
Speed of light in vacuum / Speed of light in material
Sin i / Sin r
Formula for Snell’s law?
Sin i / Sin r
i= Angle of incidence
r= Angle of refraction
Define total internal reflection?
The complete reflection of a light ray reaching an interface with a less dense medium when the angle of incidence exceeds the critical angle.
What condition has to be met for total internal reflection to happen?
The angle of incidence must exceed the critical angle