A concave mirror is placed on table in such a way that it's principal axis remains vertically upwards.P and C are respectively pole and centre of curvature of mirror.NOw a point like object is placed on C .So it's real image is also formed on c.Now if water is poured in mirror then what will be nature of image and where it will be formed?

The focal length of concave mirrors filled with Water works as a polished Plano convex lens.So it`s focal length f=(2n)/R ; n is refractive index of waterObjects distance u=-2R and f=-(2n)/RUse mirror formula to find Image distance.Put all the values and ans v= -R/1.66Image distance is less than R so image will be formed in between C and P