In the circuit shown, current (in \(A\)) through \(50\; V\) and \(30\; V\) batteries are, respectively

Moment of inertia of a cylinder of mass \(M,\) length \(L\) and radius \(R\) about an axis passing through its centre and perpendicular to the axis of the cylinder is \(I = M \left(\frac{ R ^{2}}{4}+\frac{ L ^{2}}{12}\right) .\) If such a cylinder is to be made for a given mass of material, the ratio \(\frac LR\) for it to have minimum possible \(I\) is

A square loop of side \(15 \mathrm{~cm}\) being moved towards right at a constant speed of \(2 \mathrm{~cm} / \mathrm{s}\) as shown in figure. The front edge enters the \(50 \mathrm{~cm}\) wide magnetic field at \(t=0\). The value of induced emf in the loop at \(t=10 \mathrm{~s}\) will be _______.

A current loop, having two circular arcs joined by two radial lines is shown in the figure. It carries a current of \(10\, A\). The magnetic field at point \(O\) will be close to

In a conductor, if the number of conduction electrons per unit volume is \(8.5 \times 10^{28}\, m^{-3}\) and mean free time is \(25\,fs\) (femto second), its approximate resistivity is \(\left( {{m_e} = 9.1 \times {{10}^{ - 31}}\,kg} \right)\)

Match List \(I\) with List \(II\)

List - \(I\)	List - \(II\)
\((A)\) Torque	\((I)\) \({\left[\mathrm{M}^1 \mathrm{~L}^1 \mathrm{~T}^{-2} \mathrm{~A}^{-2}\right]}\)
\((B)\) Magnetic fileld	\((II)\) \(\left[\mathrm{L}^2 \mathrm{~A}^1\right]\)
\((C)\) Magneti moment	\((III)\) \({\left[\mathrm{M}^1 \mathrm{~T}^{-2} \mathrm{~A}^{-1}\right]}\)
\((D)\) permeability of free space	\((IV)\) \(\left[\mathrm{M}^1 \mathrm{~L}^2 \mathrm{~T}^{-2}\right]\)

Choose the correct answer from the options given below :

Two equal resistances when connected in series to a battery, consume electric power of \(60\,W.\) If these resistances are now connected in parallel combination to the same battery, the electric power consumed will be .............. \(W\)

Two uniform circular discs are rotating independently in the same direction around their common axis passing through their centres. The moment of inertia and angular velocity of the first disc are \(0.1 \;kg - m ^{2}\) and \(10\; rad \,s^{-1}\) respectively while those for the second one are \(0.2 \;kg - m ^{2}\) and \(5\; rad \,s ^{-1}\) respectively. At some instant they get stuck together and start rotating as a single system about their common axis with some angular speed. The Kinetic energy of the combined system is ...........\(J\)

Two bodies of mass \(4 \mathrm{~g}\) and \(25 \mathrm{~g}\) are moving with equal kinetic energies. The ratio of magnitude of their linear momentum is :

Two steel wires having same length are suspended from a ceiling under the same load. If the ratio of their energy stored per unit volume is \(1: 4,\) the ratio of their diameters is