A microscope is focused on a mark on a table, when the mark is covered by a plate of glass 2m thick, the microscope has to be raised 0.67cm for the mark to be once more in focus. Calculate the refractive index.
A
1.50
B
1.68
C
2.58
D
1.82
Verified Correct Answer: A.
Physical Principles & Numerical Solution
R = th = 2cm, d = 0.67cm
n
=
R
A
=
R
R.d
=
2
2-0.67
=
1.52
Source: Myschool Past Questions Archive (Record #55587)