Geometrical Optics Flashcards
When an object is placed greater than twice the distance away from the focal point of a convex mirror, what type of image will be produced?
A real, inverted and small image will be produced
When an object is placed between the focal point of a converging lens but not greater than twice the focal point, (2FF) what type of image will form?
A real, inverted and large image will form
When an object is placed in front of the focal point (O
A virtual upright and large image is produced.
What type of image does a concave (diverging) lens form?
A diverging lens will create a virtual image since the light rays diverge from a point but do not converge at a point.
Virtual, upright and reduced image
What’s the difference between a real and virtual image?
A real image is created from light passing through the object.
A virtual image is created from light your eyes has gathered (extrapolated)
How do you calculate focal length?
1/f=1/o+1/i
Where f is the focal length
O= the object distance from lens
I- image distance from lens
Is the focal length positive or negative for a converging lens? Diverging lens?
The focal length is always positive for a convex (converging) lens.
The focal length is always negative for a concave (diverging) lens
Will the object distance ever be negative?
Object distance is negative when there are multiple lenses involved.
When is image distance positive?
Image distance is positive when it on the opposite side of the lens from the object-when it closer/same side as your eye.
When magnification is positive, what type of image is produced? When magnification is negative?
The image is right side up if the the magnification is positive.
The image is upside down if m is negative.
M= -di/do where di is the image distance and do is the object distance.
What is the difference between reflection and refraction?
Reflection is when light will create an angle at the surface of the object.
Refraction is when light passes through a medium and creates an angle on the other side.
What is specular reflection?
This is when the incident angle (the angle at which the light hits an object) is equivalent to the reflection angle (the angle it makes as it reflects.)
øi=ør
What is diffuse reflection?
This is when light is scattered and goes in different directions. Anything that is not smooth or a mirror will diffusely reflect light
What is the index of refraction?
Index of refraction (n)= c (speed of light in a vacuum)/v (speed of light in the medium i.e. water, air, etc.)
How does Snell’s law relate the incidence angle and the refraction angle?
Snell’s law tells us that the ratio between the speed of light and the incidence angle is equal to the speed of light and the refraction angle. V1/sinø1=v2/sinø2
Or n2sinø2= n1sinø1
Where n is the index of refraction (c-speed of light in a vacuum/ v-speed of light in the medium) and Ø1 is the incidence angle and Ø2 is the refraction angle?
