MHT CET 2021 Physics Paper: 23 Sep, Shift 1

If we increase the frequency of an a.c. supply, then inductive reactance

For series LCR circuit, which one of the following is a CORRECT statement?

In an LCR series a.c. circuit, the voltage across each of the components L, C and R is 60 V. The voltage across the LC combination is

The energy of an electron in the excited hydrogen atom is $-3.4\text{ eV}$. Then according to Bohr's theory, the angular momentum of the electron in that excited state is ($h =$ Plank's constant)

In the Bohr model, an electron moves in a circular orbit around the nucleus. Considering an orbiting electron to be a circular current loop, the magnetic moment of the hydrogen atom, when the electron is in nth excited state, is

(e = electronic charge, m${}_{e}$ = mass of the electron, h = Planck's constant)

The shortest wavelength for Lyman series is 912 $\text{Å}$. The longest wavelength in Paschen series is

Two parallel plates with dielectric placed between the plates are as shown in figure. The resultant capacity of capacitor will be [A = area of plate. $t_1, t_2$ and $t_3$ are thickness of dielectric slabs, $k_1, k_2$ and $k_3$ are dielectric constants.]

In potentiometer experiment, cells of e.m.f. '$E_1$ ' and '$E_2$' are connected in series $(E_1 > E_2)$ the balancing length is $64\text{ cm}$ of the wire. If the polarity of $E_2$ is reversed, the balancing length becomes $32\text{ cm}$. The ratio $\frac{E_1}{E_2}$ is

A balanced bridge is shown in the circuit diagram. The metre bridge wire has resistance $1\ \Omega\,\text{cm}^{-1}$. The current drawn from the battery is (Internal resistance of battery is negligible)

An electron of mass '$m$' and a photon have same energy '$E$'. The ratio of de-Broglie wavelength of electron to the wavelength of photon is $(c =$ velocity of light)

When wavelength of incident radiation on the metal surface is reduced from '$\lambda_1$ ' to '$\lambda_2$', the kinetic energy of emitted photoelectrons is tripled. The work function of metal [$h =$ Plank's constant, $c =$ velocity of light]

Eddy currents are produced when

The magnitude of flux linked with coil varies with time as $\phi = 3t^{2} + 4t + 7$. The magnitude of induced e.m.f. at $t = 2\text{ s}$ is

At what rate a single conductor should cut the magnetic flux so that current of $1.5\text{ mA}$ flows through it when a resistance of $5\,\Omega$ is connected across its ends?

In hydrogen atom an electron revolves around a proton (in nucleus) at a distance 'r' m. the intensity of electric field due to the proton at distance 'r' is $5 \times 10^{11}\text{ NC}^{-1}$, the magnitude of force between the electron and proton is [charge on electron $= 1.6 \times 10^{-19}\text{ C}$]

Two charged metallic spheres are joined by a very thin metal wire. If the radius of the larger sphere is four times that of the smaller sphere, the electric field near the larger sphere is

A charged spherical conductor has radius '$r$'. The potential difference between its surface and 3 point at a distance '$3r$' from the centre is '$v$' The electric intensity at a distance '$3r$' from the centre of the conductor is

The mass of a spherical planet is 4 times the mass of the earth, but its radius (R) is same as that of the earth. How much work is done is lifting a body of mass 5 kg through a distance of 2 m on the planet? (g = 10 ms $-2$)

The radius of a planet is twice the radius of the earth. Both have almost equal average mass densities. If '$V_P$' and '$V_E$' are escape velocities of the planet and the earth respectively, then

For a perfectly black body, coefficient of emission is

The temperature of a black body is increased by $50\%$, then the percentage increase in the rate of radiation by the body is approximated

If $m$' represents the mass of each molecules of a gas and $T$' its absolute temperature then the root mean square speed of the gas molecule is proportional to

A bar magnet has length $3\text{ cm}$, cross-sectional area $2\text{ cm}^2$ and magnetic moment $3\text{ Am}^2$. The intensity of magnetisation of bar magnet is

A student is throwing balls vertically upwards such that he throws the $2$nd ball when the $1$st ball reaches maximum height. If he throws balls at an interval of 3 second, the maximum height of the balls is $\left(g = 10\,\frac{\text{m}}{\text{s}^2}\right)$

A thin ring of radius '$R$' meter has charge '$q$' coulomb uniformly spread on it. The ring rotates about its axis with a constant frequency of $f$ revolution/s. The value of magnetic induction in $\text{Wb m}^{-2}$ at the center of the ring is ($\mu_0 =$ Permeability of free space)

An electron is projected along the axis of circular conductor carrying current '$\mathrm{I}$' The electron will experience

A particle performing S.H.M. when displacement is '$x$', the potential energy and restoring force acting on it are denoted by '$E$' and '$F$' respectively. The relation between $x, E$ and $F$ is

A body is performing S.H.M. of amplitude 'A'. The displacement of the body from a point where kinetic energy is maximum to a point where potential energy is maximum, is

A particle executing S.H.M starts from the mean position. Its amplitude is 'A' and time period '$T$'. At what displacement its speed is one-fourth of the maximum speed?

The magnifying power of a refracting type of astronomical telescope is '$m$'. If focal length of eyepiece is doubled then the magnifying power will become

A ray of light travels from air to water to glass and again from glass to air. Refractive index of water w.r.t. air is 'X', glass w.r.t. water is 'Y' and air w.r.t. glass is 'Z'. Which one of the following is correct?

Figure shows triangular lamina which can rotate about different axes moment of inertia is maximum, about the axis

Three solid spheres each of mass '$M$' and radius '$R$' are arranged as shown in the figure. The moment of inertia of the system about YY' will be

A molecule consists of two atoms each of mass '$m$' and separated by a distance '$d$'. At room temperature, if the average rotational kinetic energy is '$E$' then the angular frequency is

In common emitter amplifier, a change of 0.2 mA in the base current causes a change of 5 mA in the collector current. If input resistance is 2 k$\Omega$ and voltage gain is 75, the load resistance used in the circuit is

The resultant gate and its Boolean expression in the given circuit is

What are the values of the currents flowing in each of the following diode circuits $\text{X}$ and $\text{Y}$ respectively? (Assume that the diodes are ideal)

Water rises to a height of $2\text{ cm}$ in a capillary tube. If cross-sectional area of the tube is reduced to $\frac{1}{16}$th of initial area then water will rise to a height of

Work done in increasing the size of a soap bubble from radius of $3\text{ cm}$ to $5\text{ cm}$ in millijoule is nearly (surface tension of soap $= 0.03\text{ N m}^{-1}$)

Which one of the following statements is wrong for an isobaric process?

An ideal gas at pressure '$p$' is adiabatically compressed so that its density becomes twice that of the initial. If $\gamma = \frac{c_p}{c_v} = \frac{7}{5}$, then final pressure of the gas is

Two rods of different metals have coefficients of linear expansion '$\alpha_1$' and '$\alpha_2$' respectvely. Their respective lengths are '$\text{L}_1$' and '$\text{L}_2$'. At all temperatures ($\text{L}_2 - \text{L}_1$) is same. The correct relation is

The speed of a ball of radius $2\text{ cm}$ in a viscous liquid is $20\text{ cm/s}$. What will be the speed of a ball of radius $1\text{ cm}$ in same liquid?

Two waves $Y_1 = 0.25\sin 316t$ and $Y_2 = 0.25\sin 310t$ are propagation same direction. The number of beats produced per second are

The fundamental frequency of an air column in pipe 'A' closed at one end coincides with second overtone of pipe 'B' open at both ends. The ratio of length of pipe 'A' to that of pipe 'B' is

Two waves are represented by the equation, $y_1 = A\sin(\omega t + kx + 0.57)\text{m}$ and $y_2 = A\cos(\omega t + kx)\text{m}$, where $x$ is in metre and $t$ is in second. What is the phase difference between them?

In the interference experiment using a biprism, the distance of the slits from the screen is increased by $25\%$ and the separation between the slits is halved. If '$W$' represents the original fringewidth, the new fringewidth is

In biprims experiment, the $4$th dark band is formed opposite to one of the slits. The wavelength of light used is $(d =$ distance between the slits, $D =$ distance between scource and the screen)

In Young's experiment with a monochromatic source and two slits, one of the slits is covered with black opaque paper, the fringes will