expression for magnification power of terrestrial microscope
Answers
Answered by
0
Explanation:
Where, O→ Objective, E→ Eye lens, L→ Inverter, PQ→ Image.
Derivation of magnifying power: As the object is situated far away, hence visual and formed on the objective is equal to the visula angle formed on the eyepiece.
As the angles α and β are very small. Hence tanα≈α and tanβ≈β.
∴m=
α
β
=
tanα
tanβ
......(i)
In figure, tanα=
OQ
PQ
and tanβ=
Q
′
O
′
P
′
Q
′
But PQ=−P
′
Q
′
, OQ=f
0
and O
′
Q
′
=−u
e
Then tanα=
f
0
−P
′
Q
′
and tanβ=
−u
e
P
′
Q
′
Putting the values of tanα and tanβ in equation (i), we get
m=
f
0
−P
′
Q
′
−u
e
P
′
Q
′
=
−u
e
P
′
Q
′
×
−P
′
Q
′
f
0
m=
u
e
f
0
Similar questions