Okay, 90% of this is nonsense besides the numbers maybe.
Answer:
(a). Index of refraction are
= 1.344 &
= 1.406
(b). The velocity of red light in the glass
2.23 ×
The velocity of violet light in the glass
2.13 ×
Explanation:
We know that
Law of reflection is

Here
= angle of incidence
= angle of refraction
(a). For red light
1 ×
=
× 
= 1.344
For violet light
1 ×
=
× 
= 1.406
(b). Index of refraction is given by

= 1.344


2.23 ×
This is the velocity of red light in the glass.
The velocity of violet light in the glass is given by

2.13 ×
This is the velocity of violet light in the glass.
Gravity is also called gravitation
NOTE: The given question is incomplete.
<u>The complete question is given below.</u>
A student measures the speed of yellow light in water to be 2.00 x 10⁸ m/s. Calculate the speed of light in air.
Solution:
Speed of yellow light in water (v) = 2.00 x 10⁸ m/s
Refractive Index of water with respect to air (μ) = 4/3
Refractive Index = Speed of yellow light in air / Speed of yellow light in water
Or, The speed of yellow light in air = Refractive Index × Speed of yellow light in water
or, = (4/3) × 2.00 x 10⁸ m/s
or, = 2.67 × 10⁸ m/s ≈ 3.0 × 10⁸ m/s
Hence, the required speed of yellow light in the air will be 3.0 × 10⁸ m/s.