Question

A Convex lens of focal length 25cm and a concave lens of focal length 10cm are placed in close contact with one another.
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a) What is the power of Combination
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b) What is the focal length of Combination​

Answer 1

$\boxed{ \underline{ \underline{\footnotesize\tt{ Solution:-}}}} \: \red♡$

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$\footnotesize\tt{1) \: For \: Convex \: lens}$

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$\footnotesize\tt{Focal \: length(f) = 25cm}$

$\footnotesize\tt{Focal \: length(f) } \tt{ \: = \frac{25}{100} m}$

$\footnotesize\tt{Focal \: length(f) } \tt{ \: = 0.25m}$

$\boxed{ \underline{ \underline{\footnotesize\tt{ Focal \: length(f) } \tt{ \: = 0.25m}}}} \: \red♡$

$\: \: \: \: \: \: \: \: \: \: \: \: \:$

$\footnotesize\tt{P1 = \: } \tt{\frac{1}{f} }$

$\footnotesize\tt{P1 = \: } \tt{\frac{1}{0.25} }$

$\footnotesize\tt{P1 = \: } \tt{\frac{100}{25} }$

$\footnotesize\tt{P1 = \: } \tt{ \cancel\frac{100}{25} }$

$\footnotesize\tt{P1 = \: } \tt{ 4 }$

$\boxed{ \underline{ \underline{\footnotesize\tt{ P1 = \: } \tt{ 4 D}}}} \: \red♡$

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$\footnotesize\tt{2) \: For \: Concave \: lens}$

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$\footnotesize\tt{Focal \: length(f) = - 10cm}$

$\footnotesize\tt{Focal \: length(f) } \tt{ \: = \frac{ - 10}{100} m}$

$\boxed{ \underline{ \underline{\footnotesize\tt{ Focal \: length(f)= - 0.10m }}}} \: \red♡$

$\: \: \: \: \: \: \: \: \: \: \: \: \:$

$\footnotesize\tt{P2 = \: } \tt{\frac{1}{f} }$

$\footnotesize\tt{P2 = \: } \tt{\frac{1}{ - 0.10} }$

$\footnotesize\tt{P2 = \: } \tt{\frac{ - 100}{ 10} }$

$\footnotesize\tt{P2 = \: } \tt{ - 10.0}$

$\boxed{ \underline{ \underline{\footnotesize\tt{ P2 = \: } \tt{ - 10 D}}}} \: \red♡$

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$\footnotesize\tt{Therefore \: Power \: of \: Combination}$

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$\footnotesize\tt{P =P1 + P2 }$

$\footnotesize\tt{ \: \: \: =4 + ( - 10)}$

$\footnotesize\tt{ \: \: \: =4 - 10}$

$\boxed{ \underline{ \underline{\footnotesize\tt{ \: \: \: = - 6 D}}}} \: \red♡$

$\: \: \: \: \: \: \: \: \: \: \: \: \:$

$\footnotesize\tt{Now,P = \: } \tt{ \frac{1}{f} }$

$\footnotesize\tt{f=\: } \tt{ \frac{1}{P} }$

$\footnotesize\tt{ f=\: } \tt{ \frac{1}{ - 6} \: m}$

$\boxed{ \underline{ \underline{\footnotesize\tt{ f=\: - 0.166m}}}} \: \red♡$

Answer 2

$\huge\underline\bold\red{♡Answer♡}$

A lysosome is a small vesicle-like eukaryotic organelle. It contains hydrolytic enzymes that break down waste material and cellular debris. Lysosomes digest excess or worn-out organelles, food particles and engulfed viruses or bacteria. Thus, they are called as disposal system of the cell.