The value of escape velocity on a certain planet is $2 \, km/s$. Then the value of orbital speed for a satellite orbiting close to its surface is

An element $P$ has atomic number $56$. What will be the formula of its halide?

The spectrum of a black body at two temperatures $27^oC$ and $327^oC$ is shown in the figure. Let $A_1$ and $A_2$ be the areas under the two curves respectively. The value of $\frac{A_2}{A_1}$ is

What is meant by $Tin$ plague?

$A$ particle of mass $m$ and charge $q$ moves with a constant velocity $v$ along the positive $x$-direction. It enters a region containing a uniform magnetic field $B$ directed along the negative $z$-direction,extending from $x = a$ to $x = b$. The minimum value of $v$ required so that the particle can just enter the region $x > b$ is

At higher altitude,the boiling point of water is $95\, ^oC$. The amount of $NaCl$ added to $1\, kg$ of water $(K_b = 0.52\, K\, kg\, mol^{-1})$ in order to raise the boiling point of the solution to $100\, ^oC$ (assuming $90\%$ ionization of $NaCl$) is .......... $g$.