Solutions - CBSE Class 10 Sample Paper for 2022 Boards - Science [MCQ]

CBSE Class 10 Sample Paper Science Solution - For 2024 Boards →
Science Class 10
Solutions to CBSE Sample Paper - Science Class 10

Question 39 - Solutions - CBSE Class 10 Sample Paper for 2022 Boards - Science [MCQ] - Solutions to CBSE Sample Paper - Science Class 10

Last updated at August 14, 2026 by

If the power of a lens is - 4.0 D, then it means that the lens is a 

(A) concave lens of focal length -50 m 

(B) convex lens of focal length +50 cm 

(C) concave lens of focal length -25 cm 

(D) convex lens of focal length -25 m 

 

Answer - 

If the power of a lens is - 4.0 D, then it means that lens is a [MCQ] - Solutions - CBSE Class 10 Sample Paper for 2022 Boards - Science [MCQ]

part 2 - Question 39 - Solutions - CBSE Class 10 Sample Paper for 2022 Boards - Science [MCQ] - Solutions to CBSE Sample Paper - Science Class 10 - Class 10

So, the correct answer is (c)  

 

 

Remove Ads
Teachoo · Class 10 Explore Class 10

Transcript

Question 39 If the power of a lens is − 4.0 D, then it means that the lens is a (A) concave lens of focal length −50 m (B) convex lens of focal length +50 cm (C) concave lens of focal length −25 cm (D) convex lens of focal length −25 m Now, Power of lens = 𝟏/𝒇 Here, focal length is in meter Since Power = −4D 𝟏/𝒇 = −4 (−1)/𝑓 = f f = (−1)/4 m Converting in cm f = (−1)/4 × 100 cm f = −25 cm Since focal length is negative ∴ it is a concave lens So, the correct answer is (C)

Maninder Singh's photo - Co-founder, Teachoo

Made by

Maninder Singh

CA Maninder Singh is a Chartered Accountant with 16+ years of practical experience and 20+ years of teaching experience. He teaches Science, Economics, Accounting and English at Teachoo using clear explanations and exam-focused methods students can trust.

For faster and distraction-free study, students can choose Teachoo Black.