بدون تحميل أهم 100 سؤال فى مادة فيزياء لغات - الجزء الرابع

أهم 100 سؤال فى مادة الفيزياء لغات - الجزء الرابع



First; Definitions of the scientific concepts


A-


1) The change in the path of light ray when it passes through two
media different from each other in optical density owing to the change
in velocity.

Refraction of light


2) The ratio between the speed of light in free space to the speed of light in a certain medium.

Absolute refractive index


3) The ratio between the absolute refractive index of the second
medium (n2) to the absolute refractive index of the first medium (n1).

Relative refractive Index


4) The angle of incidence in the denser medium that corresponds to an angle of refraction in the less dense medium equal to 90º.

The critical angle


5) The product of the absolute refractive index of the incidence
medium and sine the angle of incidence equals the product of the
absolute refractive index of refraction medium and sine the angle of
refraction”.

Snell’s law


6) The deviation of light from its straight line path when it
passes through narrow slit with suitable size or touches sharp edge.

Diffraction


7) An optical phenomenon produced due to superposition of light waves produced from two coherent sources.

Interference of light


8) The illuminated and dark regions resulting from the
superposition of two waves of the same frequency, amplitude and are in
phase.

Interference fringes


9) Optical sources which produce light waves having the same frequency, amplitude and propagate in phase.

Coherent light sources


10) An optical phenomenon Happens when light ray travels from an
optically dense medium (as water) to a less dense medium as air with an
angle of incidence greater than the critical angle. (φ>φc )

Total internal reflection


11) Natural phenomenon occurs in the deserts or paved high ways
under a hot sun in which the images of objects seem as if it were a
body inverted and suspended in water in the same position of the object.

Mirage


12) The angle between the produced extended parts of the incident ray and the emergent ray in a triangular prism.

Angle of deviation


13) A triangular prism with a small angle doesn't exceed 10º and always exist at the position of minimum deviation.

Thin prism


14) The angle confined between the extensions of two emergent rays from the prism.

Angular dispersion (width)


15) The ratio between the angular size of red and blue spectrums
to the angle of mean deviation of yellow spectrum (average deviation).

Dispersive power

 


B-What is meant by each of the following;


1. The absolute refractive index of a medium = 1.4

The ratio between the speed of light in free space (vacuum) to the speed of light in glass=1.5.


2. The critical angle between water and air =42

The angle of incidence in the optically denser medium (water)
corresponding to an angle of refraction 90° in less dense medium=42o



3. Relative refractive index between the glass and water is 0.875

The ratio between the absolute refractive index of water to the absolute refractive index of the glass =0.875


4. The dispersive power in triangular prism = 0.02

The ratio between the angular size (width) of blue and red spectrums to the average deviation of yellow spectrum =0.02


5. The ratio between the angular size of red and blue spectrums
to the angle of deviation of yellow spectrum (average deviation)=0.8

The dispersive power of the prism =0.8



6. The angle of deviation of triangular prism=3°

The acute angle between the produced extended parts of incident ray and the emergent ray in the prism =3o