Question

The length of a microscope is 14 cm and for relaxed eye the magnifying power is 25. The focal length of the eye piece is 5 cm. What is the distance of the object from the objective ?

• A. 0.8 cm
• B. 1.5 cm
• C. 1.8 cm
• D. 3.2 cm

Answer 1

Answer: (C)

1.8 cm

Answer 2

$L = v = f_ e\, or\, 14 = v + 5$.Hence v = 9 cm. $M=\frac{v}{u} \times \frac{D}{f_e}$ Taking D = 25 cm, we find u = 1-8 cm