Question
Physics Question on Ray optics and optical instruments
A thin convex lens of refractive index 1.5 has a focal length of 10 cm in air. When the lens is immersed in a fluid,its focal length becomes 70 cm. The refractive index of the fluid is
A
1.33
B
1.6
C
1.25
D
1.45
E
1.4
Answer
1.4
Explanation
Solution
The correct answer is (E):1.4