The Electromagnetic Spectrum is the range of all types of electromagnetic radiation, including visible light, radio waves, microwaves, infrared, ultraviolet, X-rays, and gamma rays.
Reflection: The bouncing of light off a surface.
Refraction: The bending of light as it passes from one medium to another.
Angle of Incidence: The angle between the incident ray and the normal at the surface.
Reflected Ray: The ray that bounces off the surface after reflection.
Refracted Ray: The ray that bends after passing into a new medium.
Angle of Reflection: The angle between the reflected ray and the normal.
Plane Mirror:
Size: Same size as the object
Attitude: Upright
Location: Same distance behind the mirror as the object is in front of it
Type: Virtual
Concave Mirror:
Object at Different Locations:
Beyond C: Inverted, reduced, real, outside C
At C: Inverted, same size, real, at C
Between C and F: Inverted, enlarged, real, beyond C
At F: No image (parallel rays)
Between F and Mirror: Upright, enlarged, virtual.
Convex Mirror:
Size: Smaller than the object
Attitude: Upright
Location: Virtual, behind the mirror
Type: Virtual
Converging Lens:
Object at Different Locations:
Beyond 2F: Real, inverted, smaller
At 2F: Real, inverted, same size
Between 2F and F: Real, inverted, larger
At F: No image (parallel rays)
Between F and Lens: Virtual, upright, larger.
Diverging Lens:
SALT: Virtual, upright, smaller, located on the same side as the object.
Concave Mirror: Curves inward, can produce real images depending on the object distance.
Convex Mirror: Curves outward, always produces virtual images.
Converging Lens: Thicker in the center, focuses light to a point; can produce real or virtual images.
Diverging Lens: Thinner in the center, spreads light out; always produces virtual images.
Know how to use:
Magnification (M) = Image Height (hi) / Object Height (ho)
Thin Lens Formula: 1/f = 1/do + 1/di
Converging Lens (f=45.0 mm, ho=12.5 mm, do=36.0 mm):
Calculate di and use SALT to describe the image.
Diverging Lens (f=10.0 mm, ho=12.0 mm, do=25.0 mm):
Similar calculation as above using SALT.
Definition: A measure of how much a ray of light bends when entering a material.
Formula: n = c / v (c = speed of light in vacuum, v = speed in medium).
Relation to Density: The denser the medium, the higher the refractive index.
Calculation: Speed = c / n; for n=1.92, speed of light = c / 1.92.
Given Speed = 1.96 x 10^8 m/s, calculate using n = c / v with c = 3 x 10^8 m/s.
Definition: The complete reflection of a light ray back into its original medium when it hits the boundary at an angle greater than the critical angle.
Conditions: Light must travel from a denser to a less dense medium; angle of incidence must exceed the critical angle.
Cornea: Protects the eye and helps focus light.
Lens: Focuses light onto the retina.
Retina: Receives light and converts it to signals sent to the brain.
Pupil: Regulates the amount of light entering the eye.
Iris: Controls the size of the pupil.
Myopia (Nearsightedness): Light focuses in front of the retina; can be corrected with diverging lenses.
Hyperopia (Farsightedness): Light focuses behind the retina; can be corrected with converging lenses.
Astigmatism: Irregular lens curvature, causing distorted images; corrected with specially shaped lenses.