List of top Questions asked in KEAM- 2021

In an electromagnetic wave, the oscillating electric and magnetic field vectors are oriented in
Electromagnetic waves against their detection devices are matched below. The mismatch is
The total intensity of earth's magnetic field at the poles is 7 units. Its value at the equator is
Among vadous circuits coDstructed with rcsistor _R, inductor _L and capacitor C, the cicuit that gives maximum power dissipation is
If air core is replaced by an iron core in an inductor, its self-inductance is increased from 0.02 mH to 40 mH. The relative permeabiliry of iron is
If $B_c$ is the magnetic induction at the ceflte ofa circular coit carrying curreflt, then the magnetic induction at a poitrt oo the axis of the coil at a distance equal to the radius of the coil is
The hard ferromagnetic material among the following is
In Cyclotron, the frequency of revolution ofthe charged particle in a magnetic field is independent of
A current carrying coil placed in a magnetic field B experiences a torque τ. If θ is the angle between the normal to the plane of the coil and field B and φ is the flux linked with the coil, then
A conductor of length 20 cm carrying a curent of 5A is placed at an angle of 30° to the extemal magnetic field of 0.5 T. The.force acting on it is
A Wheatstone network is balanced with respective resisto$ 5Ω. l0Ω. 20 Ω and 40 Ω in tbe P. 0. R and S arms. If a 40 Ω) resisror is connecred across S arm. Then the bridge is again balanced by connecting
The magnitude of tfie drift velocity per unit electric field is defined as
The ratio of the magnitudes of electrostatic force between two protons at a distarce r apart to that between two electrons at the same distance of separation is
An air capacitor and identical capacitor filled with dielectric medium of dielectric constant 5 are connected in series to a voltage source of 12V. The fall of potential across $C_1$ and $C_2$ are respectively
The electric potential at a point at a distance r due to an eclectic dipole is proportional to
When two sound waves of slightly different ftequencies $f_1$ and $f_2$ are sounded together, then the time interval between successive maxima is
The solution set of the inequality 5(4x+6) <25x+10 is
If the inequality -13 ≤ x ≤ 5 is expressed in the form |x-a|≤b, then the values of a and b are respectively
Let \(\begin{vmatrix} x-1&2&1\\2&x-1&2\\1&x+2&x-1 \end{vmatrix}=ax^3+bx^2+cx+d\), where a,b,c and d are constants. Then the value of d is
The matrix \(\begin{bmatrix} -2&1&0\\3&4&1\\-4&\lambda&0 \end{bmatrix}\) is non-singular for \(\lambda\ne\)
If \(AB=\begin{bmatrix} 4&3\\5&4 \end{bmatrix}\) and \(A^{-1}=\begin{bmatrix} 3&-2\\-1&1 \end{bmatrix}\), then B=
If \(\begin{vmatrix} 1&2&1\\0&x&-3\\2&-1&x \end{vmatrix}=0\), then the value of x are
The value of the determinant \(\begin{vmatrix} 4&4^2&4^3\\3&3^2&3^3\\2&2^2&2^3 \end{vmatrix}\)is
Let \(A+B=\begin{bmatrix} 4&1&4\\1&4&4 \end{bmatrix}\)and \(B=\begin{bmatrix} 1&0&-2\\-1&3&0 \end{bmatrix}\), then A=
The term independent of x in the binomial expansion of \((x+\frac{2}{x^3})^{20}\) is