NEET · Physics · STD 12 - 9. Ray optics and optical instruments
A microscope has an objective of focal length 2 cm , eyepiece of focal length 4 cm and the tube length of 40 cm . If the distance of distinct vision of eye is 25 cm , the magnification in the microscope is :
- A 100
- B 125
- C 150
- D 250
Answer & Solution
Correct Answer
(B) 125
Step-by-step Solution
Detailed explanation
\(\begin{array}{cl}f _0=2 cm & f _e=4 cm \\ L =40 cm & D =25 cm\end{array}\)
In the condition of normal adjustment.
\(\begin{aligned} m & =\frac{ L }{ f _0} \cdot \frac{ D }{ f _e} \\ & =\frac{40}{2} \times \frac{25}{4} \\ & =125\end{aligned}\)
In the condition of normal adjustment.
\(\begin{aligned} m & =\frac{ L }{ f _0} \cdot \frac{ D }{ f _e} \\ & =\frac{40}{2} \times \frac{25}{4} \\ & =125\end{aligned}\)
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