Question

# If the focal length of objective and eye lens are $$1.2\ cm$$ and $$3\ cm$$ respectively and the object is put $$1.25\ cm$$ away from the objective lens and the final image is formed at infinity. The magnifying power of the microscope is

A
150
B
200
C
250
D
400

Solution

## The correct option is A $$200$$$$m_{\infty}=-\dfrac{v_0}{u_0}\times \dfrac{D}{f_e}$$From $$\dfrac{1}{f_0}=\dfrac{1}{v_0}-\dfrac{1}{u_0}$$$$\Rightarrow \dfrac{1}{(+1.2)}=\dfrac{1}{v_0}-\dfrac{1}{(-1.25)}\Rightarrow v_0=30\ cm$$$$\therefore | m_{ \infty}|=\dfrac{30}{1.25}\times \dfrac{25}{3}=200$$Physics

Suggest Corrections

0

Similar questions
View More

People also searched for
View More