The balancing length for a cell is $560 \, cm$ in a potentiometer experiment. When an external resistance of $10 \, \Omega$ is connected in parallel to the cell, the balancing length changes by $60 \, cm$. The internal resistance of the cell in ohms is:

Four diatomic species are listed below. Identify the correct order in which the bond order is increasing in them:

The work function of a metal is $2 \text{ eV}$. If a radiation of wavelength $3000 \text{ Å}$ is incident on it,the maximum kinetic energy of the emitted photoelectrons is (Planck's constant $h = 6.6 \times 10^{-34} \text{ J s}$; velocity of light $c = 3 \times 10^8 \text{ m/s}$; $1 \text{ eV} = 1.6 \times 10^{-19} \text{ J}$)

In an astronomical telescope in normal adjustment,a straight black line of length $L$ is drawn on the inside part of the objective lens. The eyepiece forms a real image of this line. The length of this image is $I$. The magnification of the telescope is:

The oxidation state of $Xe$ in $XeO_3$ and the bond angle in it respectively are:

In a compound microscope,the focal lengths of the two lenses are $1.5 \, cm$ and $6.25 \, cm$. If an object is placed at $2 \, cm$ from the objective lens and the final image is formed at $25 \, cm$ from the eye lens,the distance between the two lenses is ...... $cm$.