What is preserved in a museum?

In the adjoining circuit,the potential difference across $3\, \Omega$ is ............... $V$.

The element having the electronic configuration $[Kr] 4d^{10} 4f^{14} 5s^2 5p^6 5d^2 6s^2$ belongs to

The ratio of $C_p$ and $C_v$ of a gas $'X'$ is $1.4$. The number of atoms of the gas $'X'$ present in $11.2 \ L$ of it at $NTP$ will be:

An air-cored coil has a self-inductance of $0.1 \ H$. $A$ soft iron core of relative permeability $1000$ is introduced,and the number of turns is reduced to $\left(\frac{1}{10}\right)^{\text{th}}$. The value of the new self-inductance is:

There are two holes,one each along the opposite sides of a wide rectangular tank. The cross-section of each hole is $0.01 ~m^2$ and the vertical distance between the holes is $1 ~m$. The tank is filled with water. The net force on the tank in newtons when the water flows out of the holes is (Density of water $= 1000 ~kg/m^3$,$g = 10 ~m/s^2$):