Physics Notes
DEFINITIONS
LIGHT
SOUND & WAVES
HEAT & TEMPERATURE
MECHANICS
ELECTRICITY
MODERN PHYSICS
BY STEPHANI MADUKA
, PHYSICS COURSE DEFINITIONS
BY STEPHANI MADUKA
LIGHT
Real image: an image formed by the actual intersection of light rays.
Virtual image: an image formed by the apparent intersection of light rays.
Reflection: the bouncing of light off an object.
Refraction: the bending of light as it passes from one medium to another.
Snell's Law: The ratio of the sine of the angle of incidence to the sine of the angle
of refraction is a constant.
The refractive index of a medium: is the ratio of the speed of light in a vacuum to
its speed in a specific medium.
Critical angle: The incident angle in a dense medium when the refracted angle
in a less dense medium is 90° to the normal.
Laws of Reflection:
a) The incident, reflected ray, and the normal all lie in the same plane.
b) Angle of incidence = Angle of reflection
Use of concave mirror: gives a magnified and virtual image of an object when
entering inside the focus, providing a better view (e.g: dentists to view a cavity in
a tooth, makeup)
Use of convex mirror: gives a wider field of view than a plane mirror (e.g:
rearview mirror in cars, security mirror in shops).
Total Internal Reflection: This occurs when the angle of incidence in the denser
medium is larger than the critical angle, so light is reflected back into the denser
medium.
Parallax: The difference in apparent position of an object when viewed from
different positions.
Short-Sighted Defect (Eye Defect): Can see nearby objects clearly but cannot
bring distant objects into focus. (Corrected with concave lens)
Long-Sighted Defect (Eye Defect): Can see distant objects clearly but cannot
bring nearby objects into focus. (Corrected with convex lens)
DEFINITIONS
LIGHT
SOUND & WAVES
HEAT & TEMPERATURE
MECHANICS
ELECTRICITY
MODERN PHYSICS
BY STEPHANI MADUKA
, PHYSICS COURSE DEFINITIONS
BY STEPHANI MADUKA
LIGHT
Real image: an image formed by the actual intersection of light rays.
Virtual image: an image formed by the apparent intersection of light rays.
Reflection: the bouncing of light off an object.
Refraction: the bending of light as it passes from one medium to another.
Snell's Law: The ratio of the sine of the angle of incidence to the sine of the angle
of refraction is a constant.
The refractive index of a medium: is the ratio of the speed of light in a vacuum to
its speed in a specific medium.
Critical angle: The incident angle in a dense medium when the refracted angle
in a less dense medium is 90° to the normal.
Laws of Reflection:
a) The incident, reflected ray, and the normal all lie in the same plane.
b) Angle of incidence = Angle of reflection
Use of concave mirror: gives a magnified and virtual image of an object when
entering inside the focus, providing a better view (e.g: dentists to view a cavity in
a tooth, makeup)
Use of convex mirror: gives a wider field of view than a plane mirror (e.g:
rearview mirror in cars, security mirror in shops).
Total Internal Reflection: This occurs when the angle of incidence in the denser
medium is larger than the critical angle, so light is reflected back into the denser
medium.
Parallax: The difference in apparent position of an object when viewed from
different positions.
Short-Sighted Defect (Eye Defect): Can see nearby objects clearly but cannot
bring distant objects into focus. (Corrected with concave lens)
Long-Sighted Defect (Eye Defect): Can see distant objects clearly but cannot
bring nearby objects into focus. (Corrected with convex lens)
