List of top Physics Questions asked in KEAM

Four point charges (with equal magnitude of charge of $5\, C$; but with different signs) are placed at four corners of a square of side $10\, m.$ Assuming that the square is centered at the origin and the configuration of the charges are as given in the figure, the potential and the magnitude of electric field at the origin, respectively are [ Note : $k = \frac{1}{4 \pi \varepsilon_0}$]
The phase velocity of a wave described by the equation $\Psi = \Psi_0 \, \sin (kx + \omega t + \pi / 2)$ is
A ground receiver receives a signal at $5\, MHz$, transmitted by a ground transmitter at a height of $320\, m$, which is $110\, km$ away from it. Then it can communicate through (radius of earth $R \,= \,6400 \,km$)
The number of photons emitted per second by a $60\, W$ source of monochromatic light of wavelength $663\, nm$ is $ (h=6.63\times {{10}^{-34}}Js) $
The magnification of an image by a convex lens is positive only when the object is placed
A narrow slit of width $2 \,mm$ is illuminated by monochromatic light of wavelength $500\, nm$. The distance between the first minima on either side on a screen at a distance of $1 \,m$ is
The propulsion of a rocket is based on the principle of conservation of
A radioactive sample at any instant has its disintegration rate $5000$ disintegrations per minute. After $5\, min$, the rate becomes $1250$ disintegration per minute. Then, its decay constant (per minute) is
A cyclist bends while taking turn in order to
A ball is dropped from a height $h$. If the coefficient of restitution is $e$ then to what height will it rise after jumping twice from the ground
A small spherical ball falling through a viscous medium of negligible density has terminal velocity $v$. Another ball of the same mass but of radius twice that of the earlier falling through the same viscous medium will have terminal velocity
Identify the wrong statement
A rubber cord of density $d,$ Young?s modulus $Y$ and length $L$ is suspended vertically. If the cord extends by a length $0.5\, L$ under its own weight, then $L$ is
The depth $d$ at which the value of acceleration due to gravity becomes $\frac {1} { n}$ time the value at the surface is (R be the radius of the earth)
The Carnot cycle of a reversible heat engine consists of
The power factor of $LCR$ circuit at resonance is
The amount of charge flowing per second per unit area normal to the flow is called
A paramagnetic substance of susceptibility $ 3\times {{10}^{-4}} $ is placed in a magnetic field of $ 4\times {{10}^{-4}}A{{m}^{-1}} $ . Then the intensity of .magnetization in the units of $ A{{m}^{-1}} $ is
The ratio of the respective de Broglie wavelengths associated with electrons accelerated from rest with the voltages 100 V, 200 V and 300 V is
A bullet fired into a fixed wooden block loses half of its velocity after penetrating $40\,cm$. It comes to rest after penetrating a further distance of
Find the total capacitance and total charge on the capacitors
For an ideal gas, the specific heat at constant pressure $C_P$ is greater than the specific heat at constant volume $C_V$ . This is because
$CO^-$ ion moving with kinetic energy of $20\, keV$ dissociates into $O^-$ and $C$ which move along the parent ion direction. Assuming no energy is released during dissociation, the kinetic energy of the daughters $(K.E)_{O^-}$ and $(K.E)_C$ are related as
An electron enters uniform electric field maintained by parallel plates and of value $ EV{{m}^{-1}} $ with a velocity $ v\text{ }m{{s}^{-1}}, $ the plates are separated by a distance $ d $ metre, then acceleration of the electron in the field is:
A glass tube of length $ 1.0\, m $ is completely filled with water. A vibrating tuning fork of frequency $ 500 \,Hz $ is kept over the mouth of the tube and the water is drained out slowly at the bottom of the tube. If velocity of sound in air is $ 330\,m{{s}^{-1}}, $ then the total number of resonances that occur will be