Question -
Answer -
Height of the needle, h1 = 4.5 cm
Object distance, u = −12 cm
Focal length of the convex mirror, f =15 cm
Image distance = v
Thevalue of v can be obtained using the mirror formula:Hence, the image of theneedle is 6.7 cm away from the mirror. Also, it is on the other side of themirror.
The image size is given bythe magnification formula:
Hence, magnification of the image, 
The height of the image is2.5 cm. The positive sign indicates that the image is erect, virtual, anddiminished.
Ifthe needle is moved farther from the mirror, the image will also move away fromthe mirror, and the size of the image will reduce gradually.