The speed of sound in oxygen $(O_2)$ at a certain temperature is $460 \; m/s$. The speed of sound in helium $(He)$ at the same temperature will be (assume both gases to be ideal): (in $; m/s$)

In which of the following is the hydration energy higher than the lattice energy?

Consider two statements $S_1$ and $S_2$. $S_1$: If $f(x)$ is a differentiable function with $f^{\prime}(x) = 0$ in $(a, b)$ and $f(x)$ is increasing in $(a, b)$,then $\frac{f(x)}{f^{\prime}(x)}$ is also increasing in $(a, b)$. $S_2$: Both $\sin x$ and $\tan x$ are increasing functions in $\left(0, \frac{\pi}{2}\right)$. Which of the following is true?

$A$ proton (mass $m$ and charge $+e$) and an $\alpha$-particle (mass $4m$ and charge $+2e$) are projected with the same kinetic energy at right angles to a uniform magnetic field. Which one of the following statements is true?

The kinetic energy of an electron and a proton is $10^{-32} \ J$. Then the relation between their de-Broglie wavelengths is

When two species of different genealogy come to resemble each other as a result of adaptation,the phenomenon is termed as