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Light Waves — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsLight Waves1 Mark
Question
Suppose the medium in the previous question is water. Select the correct option(s) from the list given in that question.
  1. vA > vB > vC
  2. vA < vB < vC
  3. vA = vB = vC
  4. $\text{v}_\text{B}=\frac{1}{2}(\text{v}_\text{A}+\text{v}_\text{C})$
✓

Answer

  1.  $\text{v}_\text{A}>\text{v}_\text{B}>\text{v}_\text{C}$

  2. $\text{v}_\text{B}=\frac{1}{2}(\text{v}_\text{A}+\text{v}_\text{C})$

Explanation:

Since the speed of light is a universal constant,

$\text{v}_\text{A}=\text{v}_\text{B}=\text{v}_\text{C}=3\times 10^8\text{m/s}$

$\text{v}_\text{B}=\frac{1}{2}(\text{u}_\text{A}+\text{u}_\text{C})$ This expression also implies that vA = vB = vC 

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