The area (in square units) of the region bounded by $x^2=8y$,$x=4$ and the $X$-axis is:

Which one of the following frequencies of radiation (in $Hz$) has a wavelength of $600 \ nm$?

If $f(x) = \frac{1}{\sqrt{x + 2 \sqrt{2x - 4}}} + \frac{1}{\sqrt{x - 2 \sqrt{2x - 4}}}$ for $x > 2$,then $f(11)$ is equal to

Which of the following is a latex-based alkaloid?

There is a uniform electric field of strength $10^3 \, V/m$ along the $y$-axis. $A$ body of mass $1 \, g$ and charge $10^{-6} \, C$ is projected into the field from the origin along the positive $x$-axis with a velocity of $10 \, m/s$. Its speed in $m/s$ after $10 \, s$ is (Neglect gravitation).

Pure $Si$ at $500\, K$ has equal number of electron $(n_e)$ and hole $(n_h)$ concentrations of $1.5 \times 10^{16} \,m^{-3}$. Doping by indium increases $n_h$ to $4.5 \times 10^{22} \,m^{-3}$. The doped semiconductor is of