Question

7. An object of height 4 cm is placed at a distance of 15 cm from a converging
lens of focal length 10 cm. Find the position ,nature and height of the image.
An obiectie lacadadebomm from one en​

Answer 1

Explanation:

$\bf{\underline{\underline\red{Given:-}}}$

• Height of the object = 4cm

• Object distance = 15cm

• Focal length = 10cm

$\bf{\underline{\underline\blue{To\:Find:-}}}$

• The position

• Nature

• And height of the image.

$\bf{\underline{\underline\green{Solution:-}}}$

Here converging lens - Convex lens.

In convex lens:-

• u = -ve

• v = +ve

• f = +ve

Lens formula:-

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

• u = -15cm

• f = 10cm

$\rm \longrightarrow\dfrac{1}{v} - \dfrac{1}{( - 15)} = \dfrac{1}{10}$

$\rm \longrightarrow\dfrac{1}{v} + \dfrac{1}{ 15} = \dfrac{1}{10}$

$\rm \longrightarrow\dfrac{1}{v} + = \dfrac{1}{10} - \dfrac{1}{15}$

$\rm \longrightarrow\dfrac{1}{v} = \dfrac{3 - 2}{30}$

$\rm \longrightarrow\dfrac{1}{v} = \dfrac{1}{30}$

$\rm \longrightarrow \:v = 15cm$

The distance of image is 15cm