For concave mirrors, whether the image is virtual or real depends on how large the object distance is compared to the focal length.
32.
This involved creating an experiment in which she observed how the position of a concave mirror would affect the real object that it reflected.
33.
In contrast, an object placed in front of a converging lens or concave mirror at a position beyond the focal length produces a real image.
34.
Angela Tabouri, 19, a student at Athens'Home for the Mentally Retarded, lit the torch using a polished steel concave mirror on the hill of the Pnyx.
35.
While training in France, Andreas Anagnostakis, MD, an ophthalmologist from Greece, came up with the idea of making the instrument hand-held by adding a concave mirror.
36.
He often painted with the aid of a concave mirror, and to obtain exactness looked at his subject through a frame crossed with squares of silk thread.
37.
If the rays of light coming from a farther light source reflect to any point on axis of the concave mirror, they form concentric circles in that point.
38.
In the ceremony, a silver torch is placed inside a burnished-steel concave mirror placed before an altar to Hera, a Greek goddess worshipped in Olympia during the original games.
39.
Keith Christiansen, a curator at the Metropolitan Museum of Art, read an open letter to Hockney testifying that he had gone out and bought a concave mirror at Duane Reade.
40.
Heavy clouds and sporadic rain in the mountains around the ancient birthplace of the Olympics prevented the flame from being lit by the rays of the sun in a concave mirror.
