The dependence of disturbances due to two waves on time is shown in the figure. The ratio of their intensities $I_1 / I_2$ will be

Two spheres $A$ and $B$ are kept very near to each other. $A$ is negatively charged and $B$ is earthed. The true statements are:
$(A)$ Charge on $B$ is zero
$(B)$ Potential at $B$ is zero
$(C)$ Charge is uniformly distributed on $A$
$(D)$ Charge is non-uniformly distributed on $A$

$A$ parallel plate air capacitor is charged to a potential difference of $V$. After disconnecting the battery,the distance between the plates of the capacitor is increased using an insulating handle. As a result,the potential difference between the plates:

Choose the incorrect pair for the characters given by Mendel.
Character $\quad$ Dominant $\quad$ Recessive

In the reaction of $BaO_2$ with dilute $H_2SO_4$,what are the oxidation states of the most electronegative element in the products?

Which one of the following is commonly used in the transfer of foreign $DNA$ into crop plants?