When a biconvex lens of glass having refractive index $1.47$ is dipped in a liquid,it acts as a plane sheet of glass. This implies that the liquid must have a refractive index:

$A$ thin lens made of glass (refractive index $= 1.5$) of focal length $f = 16 \; cm$ is immersed in a liquid of refractive index $1.42$. If its focal length in liquid is $f_{l}$,then the ratio $f_{l} / f$ is closest to the integer:

In an optical bench experiment, the index error is $+1 \, cm$ and $-1 \, cm$ between the object needle and lens, and between the lens and image needle, respectively. The observed values of $u$ and $v$ are $9 \, cm$ and $17 \, cm$. The focal length of the lens is ..... $cm$.

$A$ convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens material. Then its focal length will

$A$ double convex air bubble in water behaves as

Provide the object distance,image distance,type,size,and magnification for an object placed in front of a thin convex lens for different positions.