Question

What is the answer this equation
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Answer 1

refractive index=speed of light in medium/ speed of light in air

1.5=X/3(108*)

X=1.5(3)(108*)

X=4.5x (108*)

* =10 to the power 8

Answer 2

We know that,
$₁n₂$= $\frac{v₁}{v₂}$
$\therefore n_glass=\frac{3×10^8}{v_glass}$
$\implies \frac{3×10^8}{v_glass} =1.5$
$\implies v_glass= \frac{3×10^8}{1.5}$
$\implies v_glass=2×10^8m/s$