MHT CET 2021 24th September Evening Shift

A rejector circuit is the resonant circuit in which

In series LCR circuit, at resonance the peak value of current will be [\(\mathrm{E_0}\) is peak emf, R is resistance, \(\omega \mathrm{L}\) is inductive reactance and \(\omega \mathrm{C}\) is capacitive]

An alternating e.m.f. is \(\mathrm{e}=\mathrm{e}_0 \sin \omega \mathrm{t}\). In what time the e.m.f. will have half its maximum value, if '\(\mathrm{e}\)' starts from zero? (\(\mathrm{T}=\) time period, \(\sin 30^{\circ}=0.5\))

The ratio of energies of photons produced due to transition of electron of hydrogen atom from its (i) second to first energy level and (ii) highest energy level to second energy level is

The half life of a radioactive substance is 30 minute. The time taken between 40% decay and 85% decay of the same radioactive substance is

A battery is used to charge a parallel plate capacitor till the potential difference between the plates becomes equal to the e.m.f. of the battery. The ratio of the energy stored int he capacitor to the work done by the battery will be

Capacitors of capacities \(\mathrm{C}_1, \mathrm{C}_2\) and \(\mathrm{C}_3\) are connected in series. If the combination is connected to a supply of '\(\mathrm{V}\)' volt, then potential difference across capacitor '\(\mathrm{C}_1\)' is

A particle is moving along the circular path with constant speed and centripetal acceleration 'a'. If the speed is doubled, the ratio of its acceleration after and before the change is

A body of mass 'm' is moving with speed 'V' along a circular path of radius 'r'. Now the speed is reduced to \(\frac{V}{2}\) and radius is increased to '3r'. For this change, initial centripetal force needs to be

In the following electrical network, the value of 1 is

The current drawn from the battery in the given network is (Internal resistance of the battery is negligible)

A light of wavelength '\(\lambda\)' and intensity '\(\mathrm{I}\)' falls on photosensitive material. If '\(\mathrm{N}\)' photo electrons are emitted, each with kinetic energy 'E', then

In a photoelectric experiment, a graph of maximum kinetic energy \((\mathrm{KE}_{\text {max }})\) against the frequency of incident radiation (v) is plotted. If \(\mathrm{A}\) and \(\mathrm{B}\) are the intercepts on the \(\mathrm{X}\) and ...

A current 'I' produces a magnetic flux '\(\phi\)' per turn in a coil of '\(n\)' turns. Self inductance of the coil is '\(L\)'. The relation between them is

A current \(I=10 \sin (100 \pi t)\) ampere, is passed in a coil which induces a maximum emf \(5 \pi\) volt in neighbouring coil. The mutual inductance of two coils is

A rectangular loop \(\mathrm{PQMN}\) with movable arm \(\mathrm{PQ}\) of length \(12 \mathrm{~cm}\) and resistance \(2 \Omega\) is placed in a uniform magnetic field of \(0.1 \mathrm{~T}\) acting perpendicular to the plane of the loop as sh...

Three charges each of \(+1 \mu \mathrm{C}\) are placed at the corners of an equilateral triangle. If the repulsive force between any two charges is \(\mathrm{F}\), then the net force on either charge will be [\(\cos 60^{\circ}=0.5\)]

Four electric charges \(+\mathrm{q},+\mathrm{q},-\mathrm{q}\) and \(-\mathrm{q}\) are placed in order at the corners of a square of side \(2 \mathrm{~L}\). The electric potential at point midway between the two positive charges is

Pressure inside two soap bubbles are 1.01 atm and 1.03 atm. The ratio between their volumes is (Pressure outside the soap bubble is 1 atmosphere)

'n' small drops of same size fall through air with constant velocity \(5 \mathrm{~cm} / \mathrm{s}\). They coalesce to form a big drop. The terminal velocity of the big drop is

If the work done in blowing a soap bubble of volume '\(\mathrm{V}\)' is '\(\mathrm{W}\)', then the work done in blowing a soap bubble of volume '\(2 \mathrm{~V}\)' will be

The average density of the earth is [g is acceleration due to gravity]

The depth from the surface of the earth of radius \(\mathrm{R}\), at which acceleration due to gravity will be \(60 \%\) of the value on the earth surface is

The length of the seconds pendulum is lm on earth. If the mass and diameter of the planet is 1.5 times that of the earth, the length of the seconds pendulum on the planet will be nearly

Three point masses, each of mass 'm' are kept at the corners of an equilateral triangle of side 'L'. The system rotates about the centre of the triangle without any change in the separation of masses during rotation. The period of rotation ...

Which one of the following is NOT a correct expression for an ideal gas?
[\(\mathrm{C_p}=\) Molar specific heat of a gas at constant pressure,
\(\mathrm{C_v}=\) Molar specific heat of a gas at constant volume,
\(\mathrm{Y}=\) Ratio of two s...

Assume that for solar radiation, surface temperature of the sun is \(6000 \mathrm{~K}\). If Wien's constant 'b' is \(2.897 \times 10^{-3} \mathrm{~mK}\), the value of maximum wavelength will be

A metal sphere cools at the rate of \(1.5^{\circ} \mathrm{C} / \mathrm{min}\) when its temperature is \(80^{\circ} \mathrm{C}\). At what rate will it cool when its temperature falls to \(50^{\circ} \mathrm{C}\). [Temperature of surrounding ...

A monoatomic gas is suddenly compressed to \((1 / 8)^{\text {th }}\) of its initial volume adiabatically. The ratio of the final pressure to initial pressure of the gas is \((\gamma=5 / 3)\)

The molecular masses of helium and oxygen are 4 and 32 respectively. The ratio of r.m.s. speed of helium at 327\(^\circ\) to r.m.s. speed of oxygen at 27\(^\circ\) will be

Which one of the following p-V diagram is correct for an isochoric process:

Two bar magnets '\(\mathrm{P}\)' and '\(\mathrm{Q}\)' are kept in uniform magnetic field '\(\mathrm{B}\)' with magnetic moments '\(\mathrm{M_P}\)' and '\(\mathrm{M_Q}\)' respectively. Magnet 'P' is oscillating with frequency twice that of m...

A magnetic dipole of magnetic moment \(\mathrm{M}\), is freely suspended in a magnetic field of induction B. The minimum and maximum values of potential energy of the dipole, respectively are

A solenoid 2 m long and 4 cm in diameter has 4 layers of windings of 1000 turns each and carries a current of 5 A. What is the magnetic field at its centre along the axis? [\(\mu_0=4\pi\times10^{-7}\) Wb/Am]

A particle of charge 'q' and mass 'm' moves in a circular orbit of radius 'r' with angular speed '\(\omega\)'. The ratio of the magnitude of its magnetic moment to that of its angular momentum depends on

A ray of light is incident on one face of an equilateral glass prism having refractive index \(\sqrt{2}\). It produces the emergent ray which just. grazes along the adjacent face. The value of angle of incidence is $$\left(\sin 45^{\circ}=\...

A monochromatic ray of light travels through glass slab and water column. The number of waves in glass slab of thickness \(4 \mathrm{~cm}\) is the same as in water column of height \(5 \mathrm{~cm}\). If refractive index of glass is $$\frac...

White light consists of wavelengths from \(480 \mathrm{~nm}\) to \(672 \mathrm{~nm}\). What will be the wavelength range when white light is passed through glass of refractive index 1.6?

The moment of inertia of a thin uniform rod of mass 'M' and length 'L' about an axis passing through a point at a distance \(\frac{L}{4}\) from one of its ends and perpendicular to the length of the rod is

The input a.c. voltage of frequency \(60 \mathrm{~Hz}\) is applied to half-wave rectifier and also to full-wave rectifier. The output frequency in case of half-wave rectifier and that in case of full wave rectifier is respectively.

Choose the correct statement. In conductors

For a transistor, the current ratio \(\alpha_{\mathrm{dc}}=\frac{69}{70}\), the current gain \(\beta_{\mathrm{dc}}\) is

The displacement of a particle performing S.H.M. is given by \(x=5 \sin (3 t+3)\), where \(x\) is in \(\mathrm{cm}\) and \(t\) is in second. The maximum acceleration of the particle will be

Two monochromatic beams of intensities I and 4 I respectively are superposed to form a steady interference pattern. The maximum and minimum intensities in the pattern are

The path difference between two interfering light waves meeting at a point on the screen is \(\left(\frac{57}{2}\right) \lambda\). The bond obtained at that point is

A cylindrical tube open at both ends has fundamental frequency 'n' in air. The tube is dipped vertically in water so that one-fourth of it is in water. The fundamental frequency of the air column becomes

A closed organ pipe and an open organ pipe of same length produce 2 beats per second when they are set into vibrations together in fundamental mode. The length of open pipe is now halved and that of closed pipe is doubled. The number of bea...

The length and diameter of a metal wire used in sonometer is doubled. The fundamental frequency will change from 'n' to

Velocity of sound waves in air is '\(\mathrm{V}\)' \(\mathrm{m} / \mathrm{s}\). For a particular sound wave in air, path difference of 'x' \(\mathrm{cm}\) is equivalent to phase difference \(n \pi\). The frequency of this wave is

The kinetic energy of a light body and a heavy body is same. Which one of them has greater momentum?