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In finding out refractive index of glass slab the following observations were made through travelling microscope 50 vernier scale division = 49 MSD; 20 divisions on main scale in each cm For mark on paper MSR = 8.45 cm, VC = 26 For mark on paper seen through slab MSR = 7.12 cm, VC = 41 For powder particle on the top surface of the glass slab MSR = 4.05 cm, VC = 1 (MSR = Main Scale Reading, VC = Vernier Coincidence) Refractive index of the glass slab is:
- 1.42
- 1.52
- 1.24
- 1.35
Correct answer: 1.42
Solution
The correct option is 1.42 because the refractive index is calculated using the formula that incorporates the observed measurements of the main scale and vernier scale readings, which reflect the light's speed change as it passes through the glass slab. The calculations yield a refractive index value of 1.42, indicating how much the light bends when entering the glass.
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