Given
The speed of light through a medium is
![v=1.24*10^8\text{ m/s}](https://img.qammunity.org/2023/formulas/physics/college/no2ibxsmrsytt966w2aesrh3oogzg1lu79.png)
To find
The type of material
Step-by-step explanation
The velocity through a medium is given by
![v=(c)/(n)](https://img.qammunity.org/2023/formulas/physics/college/atbm46963v6aoadczf15oaapby6wv6i9ht.png)
where c is the speed of light in .
n is the refractive index of the material
Thus,
![\begin{gathered} 1.24*10^8=(3*10^8)/(n) \\ \Rightarrow n=2..419 \end{gathered}](https://img.qammunity.org/2023/formulas/physics/college/f8oa2iztv2tyvx5zgoq6p2ofqx96ri0avm.png)
Thus the refractive index is 2.419
We know diamond has a refractive index of 2.417-2.419
Conclusion
The material is diamond