Derive the formula $n / v - 1 / u = n - 1 / R$ for fractional of light at spherical surface. Symbols have usual meaning. An equiconvex lens of focal length $f$ and power $P$ is cut into two halves in thickness. What are focal length and power of each half?

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Solution

$m g = 10 N$
$M^{'} = (\frac{G M}{{(R + 4 R)}^{2}}) = 250 \times \frac{G M}{25 R^{2}}$
$= \frac{250 \times g}{25} = 100 N$
we get, $f = 100 N .$

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Derive the formula n/v−1/u=n−1/R for fractional of light at spherical surface. Symbols have usual meaning. An equiconvex lens of focal length f and power P is cut into two halves in thickness. What are focal length and power of each half?

mg=10NM′=(GM(R+4R)2)=250×GM25R2=250×g25=100Nwe get, f=100N.

Derive the formula $n / v - 1 / u = n - 1 / R$ for fractional of light at spherical surface. Symbols have usual meaning. An equiconvex lens of focal length $f$ and power $P$ is cut into two halves in thickness. What are focal length and power of each half?

$m g = 10 N$
$M^{'} = (\frac{G M}{{(R + 4 R)}^{2}}) = 250 \times \frac{G M}{25 R^{2}}$
$= \frac{250 \times g}{25} = 100 N$
we get, $f = 100 N .$