Two cylindrical vessels of equal cross-sectional area \(16\,cm ^{2}\) contain water upto herghts \(100\,cm\) and \(150\,cm\) respectively. The vessels are interconnected so that the water levels in them become equal. The work done by the force of gravity during the process, is \(......J\) [Take density of water \(=10^{3}\,kg / m ^{3}\) and \(g =10\,ms ^{-2}\) ]

Which of the following physical quantities have the same dimensions?

In the circuit shown, charge on the \(5\, \mu F\) capacitor is\(........\mu C\)

The position of a particle related to time is given by \(x =\left(5 t ^2-4 t +5\right) m\). The magnitude of velocity of the particle at \(t=2\,s\) will be \(...........ms^{-1}\)

A cylinder of mass \(M_c\) and sphere of mass \(M_s\) are placed at points \(A\) and \(B\) of two inclines, respectively (See Figure). If they roll on the incline without sipping such that their accelerations are the same, then the ratio \(\frac{{\sin \,{\theta _c}}}{{\sin \,{\theta _s}}}\) is

An ideal fluid flows (laminar flow) through a pipe of non-uniform diameter. The maximum and minimum diameters of the pipes are \(6.4 \;\mathrm{cm}\) and \(4.8 \;\mathrm{cm},\) respectively. The ratio of the minimum and the maximum velocities of fluid in this pipe is:

An astronaut takes a ball of mass \(m\) from earth to space. He throws the ball into a circular orbit about earth at an altitude of \(318.5 \mathrm{~km}\). From earth's surface to the orbit, the change in total mechanical energy of the ball is \(x \frac{\mathrm{GM}_e \mathrm{~m}}{21 R_e}\). The value of \(x\) is _______. (take \(R_{\mathrm{e}}=6370 \mathrm{~km}\) )

A conducting metal circular-wire-loop of radius \(r\) is placed perpendicular to a magnetic field which varies with time as \(B = {B_0}{e^{\frac{{ - t}}{\tau }}}\) , where \(B_0\) and \(\tau \) are constants, at time \(t = 0\). If the resistance of the loop is \(R\) then the heat generated in the loop after a long time \(\left( {t \to \infty } \right)\) is

Considering Bohr's atomic model for hydrogen atom :
(A) the energy of H atom in ground state is same as energy of \(\mathrm{He}^{+}\)ion in its first excited state.
(B) the energy of H atom in ground state is same as that for \(\mathrm{Li}^{++}\)ion in its second excited state.
(C) the energy of H atom in its ground state is same as that of \(\mathrm{He}^{+}\)ion for its ground state.
(D) the energy of \(\mathrm{He}^{+}\)ion in its first excited state is same as that for \(\mathrm{Li}^{++}\)ion in its ground state
Choose the correct answer from the options given below :