Final answer:
The question asked requires additional information to be accurately answered. As it stands, it relates to geometric optics and the refraction of light through an equilateral triangular prism, but lacks information on the precise angle of deviation or refractive index of the prism.
Step-by-step explanation:
The subject of this question is related to the field of Physics, particularly focused on geometric optics and the refraction of light. To calculate the speed of light when it passes through a medium such as a prism, we rely on the concept of the index of refraction, defined as n = c/v, where 'c' is the speed of light in a vacuum and 'v' is the speed of light in the medium. In this scenario, a ray of light is passing through an equilateral triangular glass prism. The speed of light in the prism (v) can be found by rearranging the formula to v = c/n. However we are not given the refractive index of the glass prism. It is stated that 'a ray of light passing through an equilateral triangular glass prism from air undergoes minimum deviation when the angle of incidence is 3/4th of the angle of prism', but without additional information regarding the refractive index of the prism or the amount of deviation, it is impossible to calculate the exact speed of light in the prism.
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