Question

a. Give two converging lenses of focal lengths 50 cm and 5 cm. Show with the help of ray diagram how they will be arranged to obtain a magnified image of a distant object.
b. What suggestion would you make to obtain a greater magnification?

Answer 1

As per the given question,

focal lengths of the converging lens $(f_1)=50cm$

$(f_2)=5cm$

magnification$(m)=-\dfrac{f_o}{f_e}(1+\dfrac{f_e}{D})$

$=\dfrac{50}{5}(1+\dfrac{5}{25})=10(1+\dfrac{1}{5})$

$=12$

b) Suggestion to obtain a greater magnification,

• The focal length of the objective and the eyepiece lens should be small.
• Objective should have small focal length and eye piece large.
• Both the lens should have large focal length.