Question

Q. What is the power of the combination of lenses if two thin lenses of focal
length f2 and f2 are in contact?

please don't post irrelevant answers ​

Answer 1

Given :

• f 1 and f2 are focal length of two thin lenses

To find :

• power of the combination of lenses if two thin lenses.

Formula used :

• power of lens = 1/ focal length

• Power of combination of lenses = P1 + P2 + P3..........

Solution :

Now power of thin lens(1) with focal length f1 :-

⟹ power of lens (1)= 1/ focal length

⟹ power of lens (1) = 1/( f1)

Therefore , power of thin lens(1) = P1 = 1/( f1)

Now power of thin lens(2) with focal length f2 :-

⟹ power of lens (2)= 1/ focal length

⟹ power of lens (2) = 1/( f2)

Therefore , power of thin lens(2) = P2 = 1/( f2)

⟹ Power of combination of lenses = P1 + P2

put :-

• P1 = 1/( f1)
• P2 = 1/( f2)

⟹ Power of combination of lenses = P = 1/( f1)+ 1/( f2)

Now LCM of f1 and f2 = f1 ×f2 = f1 f2

⟹ P = ( f2 + f1) /( f1 f2)

Answer :

$\dfrac{f1 + f2}{f1 \:\: f2}$

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Learn more :-

1/v + 1/u = 1/f [ for mirror ]

1/v - 1/u = 1/f [ for lense ]

magnification for spherical mirror = - v/u

magnification for lense = v/u

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Answer 2

Answer:

please give me 20 thanks and take 30 thanks.....

please dude....

Explanation:

please give me 20 thanks and take 30 thanks