In which type of mirror does an object's tip appear to touch its image when in contact with the glass?

The situation described occurs with a front surface mirror. When an object is in contact with a front surface mirror, the image appears to be directly behind the reflecting surface. This type of mirror has a reflective coating on the front, allowing the light to reflect immediately as it strikes the surface, resulting in no distortion and a clear image. Because the reflective layer is on the surface, there is no gap as you would find with other types of mirrors where the reflective surface is behind the glass. This unique characteristic leads to the effect where the tip of the object appears to touch its image at that point, creating the impression of direct contact.

In contrast, concave and convex mirrors do not offer this same effect. A concave mirror can produce a magnified image but does not allow the tip to appear as if it physically touches the image due to the curvature affecting the path of light. A convex mirror provides a diminished and wider field view, and also does not permit the same direct contact perception between the object and its image. Similarly, a plane mirror, while reflecting images accurately, places the reflective layer behind the surface glass, preventing the true contact effect described in the question. Therefore, front surface mirrors are unique in creating this specific visual interaction between an object