A candle placed 25 cm from a lens, forms an image on a screen placed 7 – McqOptions

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1.	A candle placed 25 cm from a lens, forms an image on a screen placed 75 cm on the other end of the lens. The focal length and type of the lens should be [KCET 2000]
A.	+ 18.75 cm and convex lens
B.	- 18.75 cm and concave lens
C.	+ 20.25 cm and convex lens
D.	- 20.25 cm and concave lens
Answer» B. - 18.75 cm and concave lens

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