NEET-XII-Physics
17: Light Waves
- #4The speed of yellow light in a certain liquid is 2⋅4 × 108 m s-1. Find the refractive index of the liquid.Ans : Given:
Speed of yellow light in liquid (vL)= 2⋅4 × 108 m s-1
And speed of yellow light in air speed = va
Let μL be the refractive index of the liquid
Using, `` {\,\mathrm{\,\mu \,}}_{\,\mathrm{\,L\,}}=\frac{\,\mathrm{\,speed\,}\,\mathrm{\,of\,}\,\mathrm{\,light\,}\,\mathrm{\,in\,}\,\mathrm{\,vaccum\,}}{\,\mathrm{\,velocity\,}\,\mathrm{\,of\,}\,\mathrm{\,light\,}\,\mathrm{\,in\,}\,\mathrm{\,the\,}\,\mathrm{\,given\,}\,\mathrm{\,medium\,}}=\frac{c}{{v}_{\,\mathrm{\,L\,}}}``
`` {\,\mathrm{\,\mu \,}}_{\,\mathrm{\,L\,}}=\frac{3\times {10}^{8}}{\left(2.4\right)\times {10}^{8}}=1.25``
`` ``
Hence, the required refractive index is 1.25.
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