List of top Physics Questions asked in MHT CET

A light-emitting diode (LED) is fabricated using GaAs semiconductor material whose band gap is \( 1.42 \, \text{eV} \). The wavelength of light emitted from the LED is:
A star 'A' has radiant power equal to 3 times that of the Sun. The temperature of star 'A' is \( 6000 \, \mathrm{K} \) and that of the Sun is \( 2000 \, \mathrm{K} \). What is the ratio of their radii?
In a coil, the current changes from \( -2 \, \text{A} \) to \( +2 \, \text{A} \) in \( 0.2 \, \text{s} \) and induces an emf of \( 0.1 \, \text{V} \). The self-inductance of the coil is:

An electric field is given by \( \vec{E} = (6\hat{i} + 5\hat{j} + 3\hat{k}) \, \text{N/C} \). The electric flux through a surface area \( 30\hat{i} \, \text{m}^2 \) lying in the YZ-plane (in SI units) is:

A particle is executing Simple Harmonic Motion (SHM). The ratio of potential energy and kinetic energy of the particle when its displacement is half of its amplitude will be:
The difference between threshold wavelengths for two metal surfaces \( A \) and \( B \) having work functions \( \phi_A = 9 \, \text{eV} \) and \( \phi_B = 4.5 \, \text{eV} \) is: \[ \text{(Given: } h c = 1242 \, \text{eV nm)} \]
The mass of proton, neutron, and helium nucleus are respectively \( 1.0073 \, \text{u}, 1.0087 \, \text{u}, \, 4.0015 \, \text{u} \). The binding energy of the helium nucleus is:
The fundamental frequency of a closed organ pipe of length \( 20 \, \mathrm{cm} \) is equal to the second overtone of an organ pipe open at both ends. What is the length of the organ pipe open at both ends?
A wire of length \( 1 \, \text{m} \) moving with velocity \( 8 \, \text{m/s} \) at right angles to a magnetic field of \( 2 \, \text{T} \). The magnitude of induced emf between the ends of the wire will be:
"Water is flowing through a horizontal pipe in stream line flow at the narrowest part of the pipe?"
Water is flowing through a horizontal pipe in streamline flow. At the narrowest part of the pipe:
If \( p \) is the magnitude of linear momentum of a particle executing a uniform circular motion, then the ratio of centripetal force acting on the particle to its linear momentum is given by:
In an a.c. circuit, voltage and current are given by: \[ V = 100 \sin(100t) \, \text{V} \quad \text{and} \quad I = 100 \sin\left(100t + \frac{\pi}{3}\right) \, \text{mA}. \] The average power dissipated in one cycle is:
The ratio of the mass densities of nuclei of \( ^{40}\text{Ca} \) and \( ^{16}\text{O} \) is close to:
A series LCR circuit is subjected to an AC signal of \( 200 \, \text{V}, 50 \, \text{Hz} \). If the voltage across the inductor (\( L = 10 \, \text{mH} \)) is \( 31.4 \, \text{V} \), then the current in this circuit is:
Two vessels \( A \) and \( B \) are of the same size and are at the same temperature. Vessel \( A \) contains \( 1 \, \text{g} \) of hydrogen and vessel \( B \) contains \( 1 \, \text{g} \) of oxygen. \( P_A \) and \( P_B \) are the pressures of the gases in \( A \) and \( B \) respectively. Then \( \frac{P_A}{P_B} \) is:
A mixture of one mole of monoatomic gas and one mole of diatomic gas (rigid) are kept at room temperature (\( 27^\circ \text{C} \)). The ratio of specific heat of gases at constant volume respectively is:
Find the ratio of K.E. and P.E. when a particle performs SHM when it is at \( \frac{1}{n} \) times of its amplitude from the mean position.
Two monkeys off mass 10 kg and 8 kg are moving along a vertical light rope the former climbing up with an acceleration of 2 m/second square while the latter coming down with a uniform velocity of 2 m/sec square find the tension in the rope at the fixed support
Which of the following is ferromagnetic:
In Young's double slit experiment, if the distance between the slits is doubled while keeping the wavelength and the distance to the screen constant, the fringe spacing will:
If an electron jumps from the 3rd orbit to the 2nd orbit, its wavelength is \(\lambda\). Then the wavelength of the electron when it jumps from the 4th orbit to the 3rd orbit in terms of \(\lambda\) is:
An e.m.f of 5 volts is produced by a self-inductance when the current changes at a steady rate from 3A to 2A in 1 millisecond. The value of self-inductance is:
Two monkeys of mass 10 kg and 8 kg are moving along a vertical light rope. The former is climbing up with an acceleration of \( 2 \, \text{m/s}^2 \), while the latter is coming down with a uniform velocity. Find the tension in the rope at the fixed support.
The maximum kinetic energy of the photoelectrons varies.