Question

A convex lens has focal length of 15 cm. At what distance Should the object from the lens be placed so that it forms an image at 10 cm from the
lens ? Also find the magnification produced by the lens. PLEASE GIVE ME RIGHT ANSWER​

Answer 1

AnswEr:

Given:

• F = 15

• v = - 10

To Find:

u = ?

Explanation:

= 1/f = 1/v - 1/u

= 1/u = 1/v - 1/f

Here,

f = 15 & v = -10

Now, Putting Values

= 1/u = - 1/-10 - 1/15

= 1/u = (-3 -2)/30

= 1/u = -5/30

= u = -6

____________________

Magnification:

= v/u = -10/-6

= 5/3

____________________

Answer 2

$</p><p>\tt{\red{Given \: - }}$

F = 15 cm

V = 10 cm

$\dfrac{1}{u} + \dfrac{1}{v } = \dfrac{1}{f} \\ \\ \frac{1}{v} = \frac{1}{10} - \frac{1}{15} \\ \\ v = - 6\: cm.$

.

Magnification = -5/3.