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.
Correct Answer: 225
Solution and Explanation
The correct answer is: 225
1st refraction:
\(\frac{1.5}{V_1}-0=\frac{0.5}{15}\)
\(⇒ v_1 = 45 \)cm
2nd refraction:
\(\frac{1}{v_2}-\frac{1.5}{15}=\frac{-0.5}{-15}\)
\(⇒ \frac{1}{v_2}=\frac{1}{30}+\frac{1}{10}\)
\(⇒ v2 = +7.5 \)cm
\(⇒\) Distance from centre = 22.5 cm
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Concepts Used:
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Ordinary Differential Equations is an equation that indicates the relation of having one independent variable x, and one dependent variable y, along with some of its other derivatives.
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Partial Differential Equations:
A partial differential equation is a type, in which the equation carries many unknown variables with their partial derivatives.
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Homogeneous Differential Equations:
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