First slide

The optical instruments

Question

The focal lengths of the objective and the eye –piece of a compound microscope are 2.0cm and 3.0cm respectively. The distance between the objective and the eye-piece is 15.0cm. The final image formed by the eye –piece is at infinity. The two lenses are thin. The distance in cm of the object and the image produced by the objective measured from the objective lens are respectively. (in cm)

Moderate

A

– 2.4 and 12.0
B

2.4 and 15.0
C

2.3 and 12.0
D

2.3 and 3.0

Solution

When final image is formed at infinity.
Length of the tube = $v_{0} + f_{e}$
$\Rightarrow 15 = v_{0} + 3 \Rightarrow v_{0} = 12 c m$
For objective lens $\frac{1}{f_{0}} = \frac{1}{v_{0}} - \frac{1}{u_{0}}$
$\Rightarrow \frac{1}{(+ 2)} = \frac{1}{(+ 12)} - \frac{1}{u_{0}} \Rightarrow u_{0} = - 2.4 c m$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App