List of top Questions asked in KEAM

The empirical formula of a metal oxide which has $54\%$ metal (M) and $46\%$ oxygen (O) is (Atomic mass of M = $27$ amu and O = $16$ amu)

Which of the following elements have the highest and the lowest first ionization enthalpy?
(i) Be (ii) B (iii) C (iv) N (v) O

The threshold wavelength of a metal is \(6000\ \text{\AA}\). The work function of the metal is (\(h = 6.62 \times 10^{-34}\ \text{J s}\))

The radius of the first orbit of \(\mathrm{He^+}\) is

In Mosley experiment, the X-ray spectrum is obtained by plotting

If a radiation of energy $5.2$ eV falls on the photosensitive surfaces of Mo and Ni, they emit photoelectrons with maximum kinetic energy of $0.5$ eV and $1$ eV, respectively. Then the work function of

The difference in magnitudes of angular momentum of the electrons revolving in \(5^{\text{th}}\) Bohr’s orbit and \(3^{\text{rd}}\) Bohr’s orbit of hydrogen atom is

Four ideal diodes are connected as shown then the current drawn from the battery is

If the de Broglie wavelength associated with an electron is $0.1227$ nm, then its accelerating potential is

Intrinsic semiconductors Ge or Si doped with

If a radioactive parent nucleus \({}^{236}_{94}X\) emits two alpha particles and two \(\beta\) particles successively to reach the daughter nucleus \({}^{a}_{b}Y\), then the values of \(a\) and \(b\) are

An object placed at $10$ cm in front of a concave mirror of focal length $8$ cm gives image of magnification of

The magnifying power of a telescope of length $76$ cm in the normal adjustment is $75$. Then the focal lengths of the objective and eyepiece lenses are, respectively,

Two identical transformers \(A\) and \(B\) each with \(\dfrac{N_p}{N_s} = 2\) are connected such that the secondary output obtained from \(A\) is given as the primary input voltage for \(B\). If the primary ac voltage of \(A\) is \(200\) V, then the secondary voltage from \(B\) is

Microwaves are

The fringe width obtained in a given Young’s double slit experimental set up for red light, blue light and green light are, respectively, $\beta_R$, $\beta_B$ and $\beta_G$. Then

If a current carrying circular loop is suspended in a uniform magnetic field \(\vec{B}\), then

The flow of current of \(2\) A through a straight solenoid of length \(2\) m produces a magnetic field of \(2\pi \times 10^{-4}\) T at its centre. Then the number of turns in the solenoid is

In a uniform magnetic field \(\vec{B}\), a bar magnet of magnetic moment \(M\) is kept suspended at an angle of \(60^\circ\) with respect to \(\vec{B}\). The work done to turn it from \(60^\circ\) to \(90^\circ\) with respect to the field is

A wire of length $4$ m carrying a current of $1$ A is bent to form a circular loop. The magnetic moment of the loop (in A m$^2$) is

Three cells of $3$ V, $4$ V and $4$ V with respective internal resistances $0.5\,\Omega$, $0.75\,\Omega$ and $0.75\,\Omega$ are connected in series to a resistor of $4\,\Omega$. Then the current in the circuit is

The plane of a circular loop of area \(150\ \text{cm}^2\) is perpendicular to a uniform magnetic field of \(0.5\) T. If the loop is turned such that its plane is in the direction of the field in \(0.5\) s, then the induced emf produced is

The equipotential surface of a system of two point charge $5\,\mu C$ and $-5\,\mu C$ at points $A$ and $B$ separated by $80$ cm is a plane perpendicular to the line connecting $A$ and $B$ at

The ratio of the rate of flow of electrons through three resistors connected in parallel to a voltage source $V$ is $3 : 2 : 1$, then the ratio of their respective resistance values is

The ratio of the heat produced in a $2\,\Omega$ and a $4\,\Omega$ resistor connected in series with a voltage source of $12$ V is