We did an experiment with a concave mirror Concave mirror was placed on optics bench and a candle was placed at designated spots. A screen was used to see where the image was projected. But a strange thing happened. When the object was placed at the focal point, image was projected on the screen very far back of the bench. In theory, when the object is placed at the focus, no image is formed but in this experiment, image did form Can anyone explain why this happened????