An object is kept 5 cm in front of a concave mirror of focal length 15 cm. What will be the nature of the image?

For a concave mirror, the nature of the image depends on the object's position relative to the focal length (f). In this case, the focal length is 15 cm and the object is placed at 5 cm. Since the object distance (u = 5 cm) is less than the focal length (f = 15 cm), the object is located between the pole and the principal focus [t2][t6]. According to the mirror formula (1/f = 1/v + 1/u), when an object is placed within the focal length of a concave mirror, the image distance (v) becomes positive, indicating the image is formed behind the mirror [c1][c2]. Such an image is virtual and erect [t1][t5]. Furthermore, for objects placed between the focus and the pole, the magnification is greater than one, meaning the image is magnified [t4][t5]. Therefore, the image is virtual and magnified.

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 9: Light – Reflection and Refraction > 9.2.4 Mirror Formula and Magnification > p. 143
2. [2] Science , class X (NCERT 2025 ed.) > Chapter 9: Light – Reflection and Refraction > What you have learnt > p. 159