Focal length of the plano-convex lens is 15 cm. A small object is placed at A as shown in the figure. The plane surface is silvered. The image will form at `

Options

A. 60 cm left of AB
B. 30 cm left from AB
C. 12 cm left of AB
D. 60 cm right of AB

Answer

C

Explanation

` - ( 1 ) /( F) = ( 2 ) /( f ) + ( 1 ) /( oo) `
` F = - ( 15 ) /( 2 ) - ( 2 ) /( 15 ) = ( 1 ) /( v ) - ( 1 ) /( 20 ) `
` rArr v = -12 cm ` i.e. 12 cm left of AB