SATHEE: Optics Question 113

Optics Question 113

Question: A convex lens of focal length 30 cm and a concave lens of 10 cm focal length are placed so as to have the same axis. If a parallel beam of light falling on convex lens leaves concave lens as a parallel beam, then the distance between two lenses will be

Options:

A) 40 cm

B) 30 cm

C) 20 cm

D) 10 cm

Show Answer

Answer:

Correct Answer: C

Solution:

Let distance between lenses be $x$ . As per the given condition, combination behaves as a plane glass plate, having focal length $\infty$ . So by using $\frac{1}{F} = \frac{1}{f_{1}} + \frac{1}{f_{2}} - \frac{x}{f_{1} f_{2}}$

$\Rightarrow$ $\frac{1}{\infty} = \frac{1}{+ 30} + \frac{1}{- 10} - \frac{x}{(+ 30) (- 10)} \Rightarrow x = 20$ $c m$

पिछला

अगला

गोपनीयता नीति

द्वारा संचालित Prutor@IITK

sathee@iitk.ac.in

SATHEE का मीडिया कवरेज

खेल स्टोर

ऐप स्टोर

Ask SATHEE

Welcome to SATHEE !
Select from 'Menu' to explore our services, or ask SATHEE to get started. Let's embark on this journey of growth together! 🌐📚🚀🎓

I'm relatively new and can sometimes make mistakes.
If you notice any error, such as an incorrect solution, please use the thumbs down icon to aid my learning.
To begin your journey now, click on "I understand".

Optics Question 113

Question: A convex lens of focal length 30 cm and a concave lens of 10 cm focal length are placed so as to have the same axis. If a parallel beam of light falling on convex lens leaves concave lens as a parallel beam, then the distance between two lenses will be

Options:

Answer:

Solution:

इंजीनियरिंग की तैयारी

चिकित्सा तैयारी

एनसीईआरटी पुस्तकें और समाधान

महत्वपूर्ण संसाधन

अन्य संसाधन

पाठ्यक्रम

परीक्षा मंच

नमूना मॉक टेस्ट

सदस्यता

एनसीईआरटी व्यायाम वीडियो समाधान

Menu