Study Set Content:
The relation between the refraction of the light between the air and the medium is given by
Snell’s law:
Snell’s law:
n = sin i/sin r
n =
Refractive index
sin i =
angle of incidence;
sin r =
angle of refraction.
SNELL’S LAW • Also known as
The Law of Refraction.
It is often used in refractometry to describe the relationship angles of
incidence and light.
Used to determine the direction of light rays through () with varying indices of refraction.
refractive media
• The indices of refraction of the media, labelled n1, n2 and so on, are used to represent the factor by which a light ray’s speed () when travelling through a refractive medium,
decreases
The indices of refraction of the media, labelled n1, n2 and so on, are used to represent the factor by which a light ray’s speed decreases when travelling through a refractive medium, such as glass or water, as opposed to its () in a vacuum.
velocity
INSTRUMENTATION
Refractometer
Interferometer
based on the measurement of critical ray (angle) or by displacement of image.
Refractometer
used interference phenomenon to find out RI.
. Interferometer
It is the instrument used to measure refractive index (RI).
REFRACTOMETER
It measures the extent to which liquid is bent when it moves from
air into a sample
Refractive index is a() number, between () and() for most compounds,
unitless, 1.3000 and 1.700
The main principle involved is the measurement of the critical angle.
. Traditional handheld refractometer
2. Abbes Refractometer
The main principle involved is the measurement of the critical angle.
Traditional handheld refractometer
This is a benchtop refractometer, designed by (), which provides high accuracy.
Ernst Abbe
n this refractometer, the sample is held between the illuminating prism and the refracting prism
Abbes Refractometer
