List of top Questions asked in KEAM

Which of the following statements are incorrect about boundary surface diagram of orbital?} (i) A boundary surface is drawn in space for an orbital on which the value of probability density $|\Psi|^2$ is constant.} (ii) The boundary surface for $|\Psi|^2$ and $|\Psi|$ are not identical.} (iii) The density of the dots represents the probability density of finding the electron in the region.} (iv) In $1s$ and $2s$ orbitals, the probability of finding electron at a given distance is not equal in all the directions.} (v) The $2p$ orbitals in the boundary surface diagram are not spherical.
The mass of sodium acetate required to prepare $250$ mL of $0.4$ M aqueous solution is \ (Molar mass of sodium acetate = $82$ g mol$^{-1}$)
A $250$ watt bulb emits monochromatic light of wavelength $198.78$ nm. How many photons are emitted by the bulb per second? \ (Planck’s constant = $6.626 \times 10^{-34}$ J s and velocity of light = $3 \times 10^8$ ms$^{-1}$)
Which of the following ions are isoelectronic?
The correct increasing order of number of electrons around the central atom in the following molecules is
Ripple frequency in full-wave rectifier of input frequency $f$ is:
The width of the depletion layer of a p-n junction diode
The focal length of a plane mirror is
In an n-p-n transistor, the majority charge carriers in the emitter are
The logic gate that performs the operation of an inverter is
The ground state energy of hydrogen atom is -13.6 eV. The energy of the second excited state is
A convex lens of focal length 20 cm is placed in contact with a concave lens of focal length 40 cm. The power of the combination is
The binding energy per nucleon is maximum for the nucleus
In a hydrogen atom, the radius of the $n^{th}$ Bohr orbit is proportional to
The phenomenon of total internal reflection occurs when a ray of light travels from
In Young's double slit experiment, if the distance between the slits is halved and the distance between the slits and the screen is doubled, the fringe width will become
The de Broglie wavelength of a particle of mass m and kinetic energy E is given by
The sensitivity of a moving coil galvanometer can be increased by
The core of a transformer is laminated to reduce
A dip needle vibrates in a vertical plane perpendicular to the magnetic meridian. The time period of vibration is
The electromagnetic waves used in radar systems for aircraft navigation are
In an AC circuit containing only a capacitor, the current
The magnetic field at the centre of a circular current carrying coil of radius R is B. The magnetic field at a distance R from the centre on the axis of the coil is
The drift velocity of electrons in a conductor is of the order of
The electric potential at a point on the axis of an electric dipole at a distance r from its centre is proportional to