question_answer

The image of an object formed by a mirror is real, inverted and is of magnification\[-\mathbf{1}\]. If the image is at a distance of 40 cm from the mirror, where is the object placed? Where would the image be if the object is moved 20 cm towards the mirror? State reason and also draw ray diagram for the new position of the object to justify your answer.

Answer:

Magnification is\[-1\], it means distance of the image from the mirror is same as distance of object from the mirror and it happens only when the object is placed at centre of curvature of the mirror.

\[\therefore \]      Object position: At C (centre of curvature) Object distance: 40 cm.

If the object is moved 20 cm towards the mirror then its new position would be at the focus of the mirror.

\[\therefore \]      Position of the image: At infinity,