List of top Physics Questions asked in KEAM

Threshold frequency for photoelectric effect from a metallic surface corresponds to a wavelength of 6000 \({Å}\). The photoelectric work function for the metal is \( h = 6.6 \times 10^{-34} \, {Js} \):
Four hydrogen atoms combine to form an \( ^4_2He \) atom with a release of 26.7 MeV of energy. This is:
A narrow single slit of width \( d \) is illuminated by white light. If the first minimum for violet light (\( \lambda = 4500 \, {Å} \)) falls at \( \theta = 30^\circ \), the width of the slit \( d \) in microns is (1 micron = \( 10^{-6} \) m):
The INCORRECT statement is:
The magnetic field at the centre of a circular coil having a single turn of the wire carrying current \( I \) is \( B \). The magnetic field at the centre of the same coil with 4 turns carrying the same current is:
An electromagnetic wave is propagating in a medium with velocity \( \vec{v} = v \hat{i} \). The instantaneous oscillating magnetic field of this electromagnetic wave is along positive \( z \)-direction. Then the direction of the oscillating electric field is in the:
The displacement-time graph of a moving body is a straight line making a 45\(^{\circ}\) angle with the time axis. The body moves with:
A block of mass \( M \) is placed on the floor of a lift at the center. The acceleration required for the lift to descend so that the block exerts a force of \( \frac{Mg}{4} \) on the lift floor is:
A particle of mass 40 g executes simple harmonic motion with an amplitude of 2.0 cm. If the time period of oscillation is \( \frac{\pi}{20} \) s, the total mechanical energy of the system is:
Electric conduction in a semiconductor is due to:
A ball is thrown up vertically at a speed of 6.0 m/s. The maximum height reached by the ball (Take \( g = 10 { m/s}^2 \)) is:
The energy equivalent of 1 g of a substance in joules is:
If the displacement of a body moving on a horizontal surface is 151.25 cm in a time interval of 2.25 s, then the velocity of the body in the correct number of significant figures in cm s\(^{-1}\) is:

In the circuit given below, the current is: 

Bohr atom model is invalid for:
In an LCR circuit, at resonance, the value of the power factor is:
The energy required by the electron to cross the forbidden band for Germanium is:
The current flowing from p to n side in a pn junction diode irrespective of biasing is termed:
In the electron emission process, \( _{Z}^{A}X \rightarrow _{Z+1}^{A}Y + e^{-} + \bar{\nu} \), the particle \( q \) emitted along with the electron is:
In a radioactive decay, the fraction of the number of atoms left undecayed after time \( t \) is:
The constancy of the binding energy per nucleon in medium-sized nuclei is due to:
For a given radioactive material of mean life \(\tau\) and half-life \(t_{1/2}\), the relationship between \(t_{1/2}\) and \(\tau\) is:
The wavelength of the de Broglie wave (in meter) associated with a particle of mass \(m\) moving with \(\frac{1}{10}\) of the velocity of light is (h = Planck's constant, c = velocity of light):

A parallel beam of light is incident from air at an angle \(\alpha\) on the side PQ of a right-angled triangular prism of refractive index \(\mu = \sqrt{2} \approx 1.414\). The beam of light undergoes total internal reflection in the prism at the face PR when \(\alpha\) has a minimum value of 45\(^{\circ}\). 
The angle \(\theta\) of the prism is: 

A path length of 1m in air is equal to a path length of \(x\) m in a medium of refractive index 1.5. Then the value of \(x\) (in meters) is: