$A$ convex mirror of focal length $f$ forms an image which is $1/n$ times the object. The distance of the object from the mirror is

Which proteinaceous pigment controls light-dependent activities in plants?

$A$ ball is falling freely from a height. When it reaches $10 ~m$ height from the ground,its velocity is $v_0$. It collides with the ground,loses $50 \%$ of its energy,and rises back to a height of $10 ~m$. Then the velocity $v_0$ is (in $~m/s$)

$A$ block of $3\,kg$ is initially in equilibrium and is hanging by two identical springs $A$ and $B$ as shown in the figure. If spring $A$ is cut from the lower point at $t=0$,then find the acceleration of the block in $m/s^2$ at $t=0$. (Take $g = 10\,m/s^2$)

Match the following genes of the $Lac$ operon with their respective products:
List-$I$ (Gene) | List-$II$ (Product)
$(i)$ $i$ gene | $(1)$ $\beta$-galactosidase
$(ii)$ $z$ gene | $(2)$ Permease
$(iii)$ $y$ gene | $(3)$ Repressor
$(iv)$ $a$ gene | $(4)$ Transacetylase
Select the correct option.

Identify the operation performed by the circuit given below.