With increasing principal quantum number,the energy difference between adjacent energy levels in $H$ atom

In good conductors of electricity,the type of bonding that exists is

Which of the following statements is incorrect?

The second maturation division of the mammalian ovum occurs:

$A$ particle at the end of a spring executes simple harmonic motion with a period $t_1$,while the corresponding period for another spring is $t_2$. If the period of oscillation with the two springs in series is $T$,then

$A$ uniform cylinder of length $L$ and mass $M$ having cross-sectional area $A$ is suspended,with its length vertical,from a fixed point by a massless spring such that it is half submerged in a liquid of density $\sigma$ at equilibrium position. The extension $x_0$ of the spring when it is in equilibrium is: