The pair$(s)$ of diamagnetic ions is$(are)$
$(A) \ La ^{3+}, Ce ^{4+}$ $(B) \ Yb ^{2+}, Lu ^{3+}$ $(C) \ La ^{2+}, Ce ^{3+}$ $(D) \ Yb ^{3+}, Lu ^{2+}$

$y+x^2=\frac{dy}{dx}$ has the solution

Power delivered to a mass is $P = (3t^2 - 2t + 1) \text{ W}$. The change in kinetic energy from $t = 2 \text{ s}$ to $t = 4 \text{ s}$ is $...... \text{ J}$.

$A$ plot of the kinetic energy $\left(\frac{1}{2} m v^2\right)$ of ejected electrons as a function of the frequency $(\nu)$ of incident radiation for four alkali metals $(M_1, M_2, M_3, M_4)$ is shown below.
The alkali metals $M_1, M_2, M_3$ and $M_4$ are,respectively:

The points in the set $\{z \in \mathbb{C} : \arg \left(\frac{z-2}{z-6i}\right) = \frac{\pi}{2}\}$ (where $\mathbb{C}$ denotes the set of all complex numbers) lie on the curve which is a

In an experiment on photoelectric emission from a metallic surface,the wavelength of incident light is $2 \times 10^{-7} \ m$ and the stopping potential is $2.5 \ V$. The threshold frequency of the metal (in $Hz$) is approximately (charge of electron $e = 1.6 \times 10^{-19} \ C$,Planck's constant $h = 6.6 \times 10^{-34} \ J \cdot s$):