An object and its real image are located at distances $25 cm$ and $40 cm$ respectively from the two principal focii of a convex lens on either side. The linear magnification of the image is nearly equal to

+ 1.3

No worries! We‘ve got your back. Try BYJU‘S free classes today!

- 1.3

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

+ 1.8

No worries! We‘ve got your back. Try BYJU‘S free classes today!

- 1.8

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is B $- 1.3$

Here,
$x_{1} = 25 cm, x_{2} = 40 cm$
According to Newton's formula
$f^{2} = x_{1} x_{2} = (25) (40)$
$f = \sqrt{(25) (40)} = 10 \sqrt{10} cm = 32 cm$
Object distance, $u = - (f + x_{1}) = - (32 + 25) cm = - 57 cm$
Image distance, $v = (f + x_{2}) = (32 + 40) cm = 72 cm$
Magnification, $m = \frac{v}{u} = \frac{72}{- 57} = - 1.3$

Suggest Corrections

Similar questions

Q. An object and its real image are located at distances

25 cm

and

40 cm

respectively from the two principal focii of a convex lens on either side. The linear magnification of the image is nearly equal to

Q. An object and its real image are located at distances

25 c m

and

40 c m

respectively from the two principal focii of a convex lens. The linear magnification of the image is near to

An object is placed on the principal axis of a concave lens at a distance of 40 cm from it. If the focal length of the lens is also 40 cm, find the location of the image and the magnification. [3 MARKS]

Q. An object and it's real image are located at distance

25

cm and

450

cm respectively from the two principal loci, of a lens. Calculate the focal length of the lens.

Q. An object placed at a distance of

9 c m

from first principal focus of convex lens, produces a real image at a distance of

25 c m

from its second principal focus. Then focal length of lens is

Join BYJU'S Learning Program

An object and its real image are located at distances 25 cm and 40 cm respectively from the two principal focii of a convex lens on either side. The linear magnification of the image is nearly equal to

The correct option is B −1.3 Here, x1=25 cm,x2=40 cm According to Newton's formula f2=x1x2=(25)(40) f=√(25)(40)=10√10 cm=32 cm Object distance, u=−(f+x1)=−(32+25) cm=−57 cm Image distance, v=(f+x2)=(32+40) cm=72 cm Magnification, m=vu=72−57=−1.3

An object and its real image are located at distances $25 cm$ and $40 cm$ respectively from the two principal focii of a convex lens on either side. The linear magnification of the image is nearly equal to