The dominant mechanism for the motion of charge carriers in forward and reverse biased silicon $P-N$ junction are:

Molar volume $( V_m )$ of a van der Waals gas can be calculated by expressing the van der Waals equation as a cubic equation with $V_m$ as the variable. The ratio $($in $mol dm ^{-3} )$ of the coefficient of $V_m^2$ to the coefficient of $V_m$ for a gas having van der Waals constants $a=6.0 dm ^6 atm \ mol ^{-2}$ and $b=0.060 dm ^3 mol^{-1}$ at $300 K$ and $300 atm$ is $....$ .
Use: Universal gas constant $(R)=0.082 dm ^3 atm \ mol { }^{-1} K^{-1}$

Which of the following methods uses a rotary shaker?

From a uniform wire,two circular loops are made: $(i)$ $P$ of radius $r$ and $(ii)$ $Q$ of radius $nr$. If the moment of inertia of $Q$ about an axis passing through its centre and perpendicular to its plane is $8$ times that of $P$ about a similar axis,the value of $n$ is (diameter of the wire is very much smaller than $r$ or $nr$).

$A$ wire fixed at the upper end stretches by length $l$ by applying a force $F$. The work done in stretching is

In an electroplating experiment,$m \, g$ of silver is deposited when $4 \, A$ of current flows for $2 \, min$. The amount (in $g$) of silver deposited by $6 \, A$ of current for $40 \, s$ will be