JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
A parallel beam of light is allowed to fall on a transparent spherical globe of diameter \(30 \,cm\) and refractive index \(1.5\). The distance from the centre of the globe at which the beam of light can converge is________ \(mm\)
- A \(223\)
- B \(220\)
- C \(225\)
- D \(234\)
Answer & Solution
Correct Answer
(C) \(225\)
Step-by-step Solution
Detailed explanation
\(\frac{\frac{3}{2}}{ V }-\frac{1}{\infty}=\frac{\frac{3}{2}-1}{15}\) \(\frac{3}{2 V }=\frac{1}{30}\) \(V =45 \,cm\) \(\frac{1}{ V }-\frac{3}{\frac{2}{15}}=\frac{1-\frac{3}{2}}{\frac{2}{-15}}\) \(\frac{1}{ V }-\frac{1}{10}=\frac{1}{30}\)…
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