A travelling microscope is focused on a mark on a table. If a glass block of thickness 18.0cm is placed on the mark by how many centimeters will the microscope be moved upwards so as to focus the mark once again? [refractive index of glass = 1.5]
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Correct Answer: Option D
Explanation:
Apparent depth = \(\frac{\text{thickness}}{\text{refractive index}}\)
= \(\frac{18}{1.5} = 12cm\)
Upward adjustment = 18 - 12
= 6cm
Apparent depth = \(\frac{\text{thickness}}{\text{refractive index}}\)
= \(\frac{18}{1.5} = 12cm\)
Upward adjustment = 18 - 12
= 6cm