 To obtain an erect image with a concave mirror, the object must be placed within the focal length of the mirror. For a concave mirror with a focal length of 15 cm, the object should be placed less than 15 cm from the mirror. The image formed will be virtual, erect, and larger than the object. This occurs because concave mirrors magnify objects when they are placed closer to the mirror than its focal point.

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## Introduction to Image Formation by Concave Mirrors

Basic Principles of Concave Mirrors: Concave mirrors are curved mirrors that converge light rays to a focal point. The nature of the image formed by a concave mirror depends on the object’s distance from the mirror.

### Focal Length of Concave Mirrors

Defining the Focal Point: The focal length of a concave mirror is the distance from the mirror to its focal point. For the given concave mirror, this distance is 15 cm.

Desired Image Characteristics
Requirement for an Erect Image: To obtain an erect image using a concave mirror, the object must be placed within the focal length of the mirror. This means the object should be located at a distance less than the mirror’s focal length.

#### Appropriate Object Distance

Determining the Range: For a concave mirror with a 15 cm focal length, the object should be placed anywhere less than 15 cm from the mirror. This placement ensures the formation of the desired image.

##### Nature of the Formed Image

Virtual and Erect: When the object is within the focal length of a concave mirror, the image formed is virtual and erect. This means the image cannot be projected onto a screen and appears to be upright.

###### Image Size Relative to the Object

Magnification Aspect: In this scenario, the image will also be larger than the object. Concave mirrors magnify objects when they are placed closer than the focal point, leading to an enlarged, upright image.

Therefore, to achieve an erect and magnified image with the concave mirror, the object must be positioned within 15 cm from it, resulting in a virtual, erect, and larger image.

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Questions of 10th Science Chapter 9 in Detail

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