Question

How we write holiday homework in hindi

Answer 1

Given:-

• Height of the object = 2cm
• Focal length = 20cm
• Object distance = 15cm

To Find:-

• The Magification and position of the image.

Solution:-

We know for a convex lens:-

• Focal length, f = +ve = 20cm
• Object distance = -ve = -15cm

Formula for finding image distance is given by :-

$\pink{\boxed{ \sf \leadsto \frac{1}{f} = \frac{1}{v} - \frac{1}{u} }}$

$\sf \implies \dfrac{1}{20} = \dfrac{1}{v} - \dfrac{1}{ - 15}$

$\sf \implies \dfrac{1}{20} = \dfrac{1}{v} +\dfrac{1}{ 15}$

$\sf \implies \dfrac{1}{v} = \dfrac{1}{20} - \dfrac{1}{ 15}$

$\sf \implies \dfrac{1}{v} = \dfrac{3 - 4}{60}$

$\sf \implies \dfrac{1}{v} = \dfrac{-1}{60}$

$\sf \implies v = -60cm$

$\sf \underline{\:\:\underline{\: Image \: distance \: (v) = -60cm\:}\:\:}$

$\sf Magnification = \dfrac{v}{u}$

$\sf \implies m = \dfrac{60}{-15}$

$\sf \implies m = 4$

Since, the magnification is positive

Nature of the image is:-

Virtual

Erect

Enlarged