A thin convex lens of focal length f made of | vedclass

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(C) According to the lens maker's formula,the focal length $f'$ of a lens in a medium is given by $\frac{1}{f'} = \left( \frac{\mu_c}{\mu_l} - 1 \righ

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a divergent lens

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(C) According to the lens maker's formula,the focal length $f'$ of a lens in a medium is given by $\frac{1}{f'} = \left( \frac{\mu_c}{\mu_l} - 1 \right) \left( \frac{1}{R_1} - \frac{1}{R_2} \right)$.For a convex lens in air,$\frac{1}{f} = (\mu_c - 1) \left( \frac{1}{R_1} - \frac{1}{R_2} \right)$.When immersed in a liquid with refractive index $\mu_l > \mu_c$,the term $\left( \frac{\mu_c}{\mu_l} - 1 \right)$ becomes negative because $\frac{\mu_c}{\mu_l} Since the term $\left( \frac{1}{R_1} - \frac{1}{R_2} \right)$ is positive for a convex lens,the new focal length $f'$ becomes negative.$A$ lens with a negative focal length behaves as a concave or divergent lens.

$A$ thin convex lens of focal length $f$ made of crown glass is immersed in a liquid of refractive index $\mu_l$ $(\mu_l > \mu_c)$,where $\mu_c$ is the refractive index of the crown glass. The convex lens now acts as:

Similar Questions

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When will the convergent nature of a convex lens be less as compared to its nature in air?

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