Question

Show that image distance changes when object distance changes when object is placed in front of convex lens ?

Answer 1

Explanation:

We are to use here the Lens maker's for as stated below

#1/f=(mu_2/mu_1-1)(1/r_1-1/r_2)#

Where f =focal lens of the lens

#mu_1=#refractive index of the surrounding medium

#mu_2=#refractive index of medium of the lens

#r_1=# radius of curvature of the lens of first refracting surface where the beam is incident.

#r_2=# radius of curvature of the lens of the second refracting surface through which emergent beam comes out.

Here #r_1#and #r_2# remaining same and normally #mu_2> mu_1#

If the refractive index of surrounding medium i.e. #mu_1# is increased but kept less than #mu_2# then the ratio #mu_2/ mu_1# will be diminished and as a result the focal length f will be increased.

we know

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

where v = image distance

u = object distance

object distance remaining same the image distance proportionately increases with the increase in focal length.