List of top Questions asked in KEAM- 2016

For commercial telephonic communication, the frequency range for speech signals is
The role of envelope detector in an AM receiver is to
The set of physical quantities among the following which are dimensionally different is
When the voltage and current in a conductor are measured as $(100 \pm 4)$ V and $(5 \pm 0.2)$ A, then the percentage of error in the calculation of resistance is
The graph which cannot possibly represent one-dimensional motion is
If the height of TV tower is increased by $21\%$, the transmission range is enhanced by
The range of a communication system can be extended by a
In a Zener diode regulated power supply, unregulated d.c. input of $10$ V is applied. If the resistance $R_s$ connected in series with a Zener diode is $200\,\Omega$ and the Zener voltage $V_z = 5$ V, the current across the resistance $R_s$ is
To detect light of wavelength $500$ nm, the photodiode must be fabricated from a semiconductor of minimum band gap of
The circuit shown below gives the output as that of A
The binding energy per nucleon of \( ^{16}\text{O} \) is \( 7.97 \) MeV and that of \( ^{17}\text{O} \) is \( 7.75 \) MeV. The energy in MeV required to remove a neutron from \( ^{17}\text{O} \) is
If the work functions of three photosensitive materials are 1 eV, 2 eV and 3 eV respectively, then the ratio of threshold frequencies of light that produce photoelectrons of maximum kinetic energy of 1 eV from each of them is
The electron density of intrinsic semiconductor at room temperature is \( 10^{16} \,\text{m}^{-3} \). When doped with a trivalent impurity, the electron density is decreased to \( 10^{14} \,\text{m}^{-3} \) at the same temperature. The majority carrier density is
During $\beta^-$ emission
If the ratio of the radius of a nucleus with 61 neutrons to that of helium nucleus is 3, the atomic number of this nucleus is
The magnification of an image by a convex lens is positive only when the object is placed
If the radius of curvature of the curved surface of a plano-convex lens is $50$ cm, its focal length is ($\mu = 1.5$)
$\gamma$-rays are detected by
Secondary rainbow in the atmosphere is
If the direction of electric and magnetic field vectors of a plane electromagnetic wave are along positive $y$ direction and positive $z$ direction respectively, then the direction of propagation of the wave is along
When an object is viewed with a light of wavelength \( 6000 \,\text{\AA} \) under a microscope its resolving power is \( 10^4 \). The resolving power of the microscope when the same object is viewed with a light of wavelength \( 4000 \,\text{\AA} \) is
For a diffraction from a single slit, the intensity of the central point is
A bar magnet has a period of oscillation $T$. If a similar brass piece of the same mass is placed over it, then the number of oscillations it makes in one second is
If $0.1$ J of energy is stored for the flow of current of $0.2$ A in an inductor, then its inductance value is
The self inductance of a long solenoid carrying current is independent of