The principle of immunization or vaccination is based on the property of ...........

The work function of a certain metal is $3.31 \times 10^{-19} \, J$. The maximum kinetic energy of photoelectrons emitted by incident radiation of wavelength $5000 \, \text{Å}$ is: (Given: $h = 6.62 \times 10^{-34} \, J \cdot s$, $c = 3 \times 10^8 \, m/s$, $e = 1.6 \times 10^{-19} \, C$) (in $\text{eV}$)

The area (in sq units) bounded by the curves $y^2=4x$ and $x^2=4y$ is

If $f:R \to R$ and $g:R \to R$ are defined by $f(x) = 2x + 3$ and $g(x) = x^2 + 7$,then the values of $x$ such that $g(f(x)) = 8$ are

The bond energy of $Cl_2$,$Br_2$,and $I_2$ follows the order:

The binding energy per nucleon versus mass number curve for nuclei is shown in the figure. $W, X, Y$ and $Z$ are four nuclei indicated on the curve. The process that would release energy is