Find two positions of an object, placed in front of a concave mirror of focal length 15cm, so that the image formed is 3 times the size of the object.

Find the distance of object from a concave mirror of focal length 10 cm so that image size is four time the size of the object.

Find the distance of object form a concave morror of focal length 10 cm so that image size is four times the size of the object.

Find the distance of object form a concave morror of focal length 10 cm so that image size is four times the size of the object.

Find the position of an object which when placed in front of a concave mirror of focal length 20 cm, produces a virtual image which is twice the size of the object.

Find the position of an object,which when placed in front of a concave mirror of focal length 20 cm,produces a virtual image,which is twice the size of the object.