If the distance between the centres of the Earth and the Moon is $D$ and the mass of the Earth is $81$ times the mass of the Moon,then at what distance from the centre of the Earth will the net gravitational field be zero?

......... is a living chemical.

The monomer $( X )$ involved in the synthesis of Nylon $6,6$ gives positive carbylamine test. If $10$ moles of $X$ are analyzed using Dumas method, the amount $($in grams$)$ of nitrogen gas evolved is $....$
Use: Atomic mass of $N ($in amu$) = 14$

$A$ rectangular loop has a sliding connector $PQ$ of length $l$ and resistance $R \, \Omega$. It is moving with a speed $v$ as shown. The setup is placed in a uniform magnetic field directed into the plane of the paper. The three currents $I_1$, $I_2$, and $I$ are:

The equivalent resistance between $A$ and $B$ is

The coil in a moving coil galvanometer experiences a torque proportional to the current passing through it. If a steady current $i$ is passed through it,the steady deflection of the coil is found to be $90^o$. Now,the steady current is switched off and a charge $q$ is suddenly passed through the coil. If the coil has $N$ turns of area $A$ and its moment of inertia is $I$ about the axis of rotation,then the maximum angle through which it deflects upon passing charge $q$ is: