List of top Questions asked in MHT CET- 2021

In potentiometer experiment, null point is obtained at a particular point for a cell on potentiometer wire '$x$' cm long. If length of potentiometer wire is increased by few centimeter without changing the cell, the balancing length will [Driving source is not changed]
A galvanometer has resistance '$G$' $\Omega$ and '$I_g$' is current flowing through it which produces full scale deflection. '$S_1$' is the value of shunt which converts it into an ammeter of range 0 to '$3I$' and '$S_2$' is the shunt value which converts it into an ammeter of range 0 to '$4I$', the ratio $S_2 : S_1$ is
The relation between magnetic moment 'M' of revolving electron and principle quantum number 'n' is
A hollow charged metal sphere has radius 'R'. If the potential difference between its surface and a point at a distance '5R' from the centre is V, then magnitude of electric field Intensity at a distance '5R' from the centre of sphere is
A body performs S.H.M. under the action of force '$F_1$' with period '$T_1$' second. If the force is changed to '$F_2$' it performs S.H.M. with period '$T_2$' second. If both forces '$F_1$' and '$F_2$' act simultaneously in the same direction on the body, the period in second will be
A series LCR circuit with resistance ($R$) $500\ \Omega$ is connected to an a.c. source of $250\ \text{V}$. When only the capacitance is removed, the current lags behind the voltage by $60^\circ$. When only the inductance is removed, the current leads the voltage by $60^\circ$. The impedance of the circuit is ($\tan \frac{\pi}{3} = \sqrt{3}$)
The magnetic field at the centre of a current carrying circular coil of area '$A$' is '$B$'. The magnetic moment of the coil is ($\mu_0 = $ permeability of free space)
Beats are produced by waves $y_1 = a \sin 2000\pi t$ and $y_2 = a \sin 2008\pi t$. The number of beats heard per second is
In Young's double slit experiment, the intensity at a point where the path difference is $\frac{\lambda}{4}$ ($\lambda$ is wavelength of light used) is '$I$'. If '$I_0$' is the maximum intensity then $I/I_0$ is equal to
The gyromagnetic ratio of an electron in an hydrogen atom, according to Bohr model is
The depth at which acceleration due to gravity becomes $\frac{g}{n}$ is [$R = \text{radius of earth}$, $g = \text{acceleration due to gravity}$, $n = \text{integer}$]
A rectifier is used to
Two stars 'P' and 'Q' emit yellow and blue light respectively. The relation between their temperatures ($T_P$ and $T_Q$) is
A metal wire of length $2500\ \text{m}$ is kept in east-west direction, at a height of $10\ \text{m}$ from the ground. If it falls freely on the ground then the current induced in the wire is (Resistance of wire $= 25\sqrt{2}\ \Omega, g = 10\ \text{m/s}^2$ and Earth's horizontal component of magnetic field $B_H = 2 \times 10^{-5}\ \text{T}$)
Inside a vessel filled with liquid a converging lens is placed as shown in figure. The lens has focal length $15\ \text{cm}$ when in air and has refractive index $\frac{3}{2}$. If the liquid has refractive index $\frac{9}{5}$, the focal length of lens in liquid is
A body is projected from earth's surface with thrice the escape velocity from the surface of the earth. What will be its velocity when it will escape the gravitational pull?
The surface energy of a liquid drop is 'U'. It splits up into 512 equal droplets. The surface energy becomes
A cricket player hit a ball like a projectile but the fielder caught the ball after 2 second. The maximum height reached by a ball is ($g = 10\ \text{m/s}^2$)
An air column in a pipe, which is closed at one end will be in resonance with a vibrating tuning fork of frequency 264 Hz for various lengths. Which one of the following lengths is not possible? (V = 330 m/s)
A particle is suspended from a vertical spring which is executing S.H.M. of frequency $5\ \text{Hz}$. The spring is unstretched at the highest point of oscillation. Maximum speed of the particle is ($g = 10\ \text{m/s}^2$)
Photoelectrons are emitted when photons of energy $4.2\ \text{eV}$ are incident on a photosensitive metallic sphere of radius $10\ \text{cm}$ and work function $2.4\ \text{eV}$. The number of photoelectrons emitted before the emission is stopped is
[$\frac{1}{4\pi\epsilon_0} = 9 \times 10^9\ \text{SI unit};\ e = 1.6 \times 10^{-19}\ \text{C}$]
In an ideal step down transformer, out of the following quantities, which quantity increases in the secondary coil?
A uniformly charged semicircular arc of radius $r$ has linear charge density $\lambda$. What is the electric field at its centre? ($\epsilon_0 =$ permittivity of free space)
An inductive coil has a resistance of $100\ \Omega$. When an a.c. signal of frequency $1000\ \text{Hz}$ is applied to the coil the voltage leads the current by $45^\circ$. The inductance of the coil is ($\tan 45^\circ = 1$)
Two wires carrying currents $5\ \text{A}$ and $2\ \text{A}$ are enclosed in a circular loop as shown in the figure. Another wire carrying a current of $3\ \text{A}$ is situated outside the loop. The value of $\oint \vec{B} \cdot d\vec{l}$ around the loop is ($\mu_0 = $ permeability of free space, $d\vec{l}$ is the length of the element on the Amperion loop)