JEE MAIN - Physics (2020 - 5th September Morning Slot - No. 20)
For a concave lens of focal length f, the relation
between object and image distances u and v,
respectively, from its pole can best be
represented by (u = v is the reference line) :
_5th_September_Morning_Slot_en_20_1.png)
_5th_September_Morning_Slot_en_20_2.png)
_5th_September_Morning_Slot_en_20_3.png)
_5th_September_Morning_Slot_en_20_4.png)
คำอธิบาย
$$v = {{uf} \over {u + f}}$$
Case-I
If v = u
$$ \Rightarrow $$ f + u = f
$$ \Rightarrow $$ u = 0
Case-II
If u = $$\infty $$
then v = f
So you can see both of them are equal only when v = 0 and u = 0.
Case-I
If v = u
$$ \Rightarrow $$ f + u = f
$$ \Rightarrow $$ u = 0
Case-II
If u = $$\infty $$
then v = f
So you can see both of them are equal only when v = 0 and u = 0.