Question

Please answer this question...

Answer 1

given :

magnification=m=-4[since it is real and magnified]

v= 60cm

object distance=u=?

magnification =m=V/u

u= 60/-4 =-15cm

Focal length=f=?

f=1/v - 1/u

=1/60 +1/15

=4+1/60

=5/60

f=60/5

=12cms

∴ Foal length of convex lens=12cm

Power=P=?

p=1/f (in m)

=100/f ( in cm)

=100/12

=+8.33 Diopters

Answer 2

Answer:

$4 = \frac{v}{u} \\u = \frac{60}{4} \\ u \: = 15 \\ by \: lense \: formula \: \\ \frac{1}{f} = \frac{1}{v} - \frac{1}{u} \\ \frac{1}{f} = \frac{1}{60} - \frac{1}{15} \\ f \: = - 20$

hope the answer will help you