A real image of height twice that of the object was formed at a distance of 20 cm from the pole of a concave mirror. what is the focal length of the mirror ?

A real image of height twice that of the object was formed at a distan

1.	A real image of height twice that of the object was formed at a distance of 20 cm from the pole of a concave mirror. what is the focal length of the mirror ?
A.	5.56 cm
B.	6.67 cm
C.	7.78 cm
D.	8.89 cm
Answer» C. 7.78 cm

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A real image of height twice that of the object was formed at a distance of 20 cm from the pole of a concave mirror. what is the focal length of the mirror ?

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