Learn
Games

5.5 - Image Formation by Concave Lens

Interactive Audio Lesson

Listen to a student-teacher conversation explaining the topic in a relatable way.

Introduction to Concave Lenses

Unlock Audio Lesson

Signup and Enroll to the course for listening the Audio Lesson

Teacher
Teacher

Today, we will learn about concave lenses and the images they form. What do you think happens when light hits a concave lens?

Student 1
Student 1

I think it spreads out the light, right?

Student 2
Student 2

So, does that mean the image will be smaller?

Teacher
Teacher

Yes! Concave lenses diverge light rays, which leads to the formation of virtual images. We can remember this by the mnemonic 'Diminished and Diverged' to recall that they always yield diminished images.

Characteristics of Images Formed by Concave Lenses

Unlock Audio Lesson

Signup and Enroll to the course for listening the Audio Lesson

Teacher
Teacher

What properties do the images formed by concave lenses have?

Student 3
Student 3

They are virtual and upright, right?

Student 4
Student 4

And they're smaller than the object!

Teacher
Teacher

Exactly! Virtual, erect, and diminished – VED is a good way to remember these properties!

Using the Lens Formula with Concave Lenses

Unlock Audio Lesson

Signup and Enroll to the course for listening the Audio Lesson

Teacher
Teacher

Now, let’s apply the lens formula. Can anyone tell me what it looks like?

Student 1
Student 1

It’s 1/f = 1/v - 1/u.

Teacher
Teacher

Correct! If we have an object distance (u) of -10 cm and a focal length (f) of -15 cm, how would we find the image distance (v)?

Student 2
Student 2

We rearrange it to solve for v?

Teacher
Teacher

Spot on! Let’s do the calculation together using these values.

Recapping Key Concepts

Unlock Audio Lesson

Signup and Enroll to the course for listening the Audio Lesson

Teacher
Teacher

Great job, everyone! Let’s recap. What are the main characteristics of images formed by concave lenses?

Student 3
Student 3

They are virtual, erect, and diminished!

Student 4
Student 4

And the formula we use is 1/f = 1/v - 1/u.

Teacher
Teacher

Exactly! Keep practicing with these concepts, and you’ll get the hang of it!

Introduction & Overview

Read a summary of the section's main ideas. Choose from Basic, Medium, or Detailed.

Quick Overview

This section focuses on how concave lenses form virtual and diminished images regardless of the object’s position.

Standard

In this section, we explore the image formation by concave lenses, highlighting that they create virtual, erect, and diminished images for any object placed in front of them. The relationships involving object and image distances are also discussed through the lens formula.

Detailed

Image Formation by Concave Lens

A concave lens, characterized as diverging due to its thinner center and thicker edges, plays a crucial role in optical systems. When light rays parallel to the principal axis enter a concave lens, they diverge after refraction, appearing to emanate from a focal point on the same side as the object. This section details how concave lenses uniquely create images that are virtual (cannot be projected onto a screen), erect (upright), and diminished (smaller in size) for any position of the object, which lies anywhere between the optical centre (O) and the focal point (F1). The distance relationships are governed by the lens formula:

o
ext{1/f} = 1/v - 1/u

Understanding these relationships is essential when evaluating real-world applications such as eyeglasses for nearsightedness, illustrating how concave lenses modify the path of light to enhance vision.

Youtube Videos

Convex and Concave Lenses
Convex and Concave Lenses
LENSES :CLASS 10 : CBSE & ICSE : CONVEX AND CONCAVE LENS: Characteristic of IMAGE :REFRACTION:
LENSES :CLASS 10 : CBSE & ICSE : CONVEX AND CONCAVE LENS: Characteristic of IMAGE :REFRACTION:
Refraction Through a Lens Class 10 ICSE | Light Physics ICSE Class 10 | @sirtarunrupani
Refraction Through a Lens Class 10 ICSE | Light Physics ICSE Class 10 | @sirtarunrupani
Refraction through a Lens Class 10 ICSE Physics |Selina Chapter 5| Formation of image by a lens
Refraction through a Lens Class 10 ICSE Physics |Selina Chapter 5| Formation of image by a lens
ICSE PHYSICS CLASS 10 Refraction through a Lens Chapter-5 Image Formation By Convex and Concave Lens
ICSE PHYSICS CLASS 10 Refraction through a Lens Chapter-5 Image Formation By Convex and Concave Lens
Why Does Light Bend? | Concave & Convex Lenses | The Dr Binocs Show | Peekaboo Kidz
Why Does Light Bend? | Concave & Convex Lenses | The Dr Binocs Show | Peekaboo Kidz
science experiment #science #experiment
science experiment #science #experiment
Free Best Topic l Class 10th I Physics I ICSE I Chapter 5 I Refraction through a lens l L26
Free Best Topic l Class 10th I Physics I ICSE I Chapter 5 I Refraction through a lens l L26
Master Concave Lens Image formation Ray Diagrams in 20s! 190k views!
Master Concave Lens Image formation Ray Diagrams in 20s! 190k views!
Refraction Through a Lens [ Part 1 ] | ICSE Class 10 Physics Chapter 5 | Semester 1 - Vedantu
Refraction Through a Lens [ Part 1 ] | ICSE Class 10 Physics Chapter 5 | Semester 1 - Vedantu

Audio Book

Dive deep into the subject with an immersive audiobook experience.

Image Formation Overview

Unlock Audio Book

Signup and Enroll to the course for listening the Audio Book

Position of Object Position of Image Size Nature
Anywhere Between O and F1 Diminished Virtual, erect

Detailed Explanation

The section explains how a concave lens forms images based on the position of the object in relation to the lens. The key point here is that regardless of where the object is placed, it will always form a diminished (smaller than the object) and virtual (cannot be projected on a screen) image that appears erect (upright).

Examples & Analogies

You can think of a concave lens as a funhouse mirror that creates smaller reflections of you. Just like the reflection appears erect and smaller when you stand in front of that mirror, a concave lens creates a similar effect with light and images.

Definitions & Key Concepts

Learn essential terms and foundational ideas that form the basis of the topic.

Key Concepts

  • Concave lenses diverge light rays, creating virtual images.

  • Images formed by concave lenses are always upright (erect) and diminished.

  • The lens formula (1/f = 1/v - 1/u) helps to calculate object and image distances.

Examples & Real-Life Applications

See how the concepts apply in real-world scenarios to understand their practical implications.

Examples

  • A concave lens used in eyeglasses for myopia creates a virtual and smaller image of distant objects.

  • When an object is placed 5 cm from a concave lens with a focal length of -10 cm, the image is virtual, erect, and smaller than the object.

Memory Aids

Use mnemonics, acronyms, or visual cues to help remember key information more easily.

🎵 Rhymes Time

  • Concave lenses diverge with ease, creating images that please, erect and small as you can see.

📖 Fascinating Stories

  • Imagine a little fish swimming in a world of light, looking through a concave lens. The fish sees everything around it but smaller, yet it feels just as big and happy.

🧠 Other Memory Gems

  • Use 'VED' to remember: Virtual, Erect, Diminished for concave lens images.

🎯 Super Acronyms

‘C(oncave) = D(iverge)’ helps recall that concave lenses diverge light.

Flash Cards

Review key concepts with flashcards.

Glossary of Terms

Review the Definitions for terms.

  • Term: Concave Lens

    Definition:

    A lens that is thinner in the center than at the edges and causes light rays to diverge.

  • Term: Virtual Image

    Definition:

    An image that cannot be projected onto a screen because the light rays do not actually converge.

  • Term: Erect Image

    Definition:

    An image that appears upright as opposed to inverted.

  • Term: Diminished Image

    Definition:

    An image that is smaller than the object.

  • Term: Focal Length (f)

    Definition:

    The distance from the optical center of the lens to the principal focus.