List of top Questions asked in MHT CET- 2021

A big water drop is divided into 8 equal droplets. $\Delta P_S$ and $\Delta P_B$ be the excess pressure inside a smaller and bigger drop respectively. The relation between $\Delta P_S$ and $\Delta P_B$ is
A particle is performing S.H.M. with maximum velocity $v$. If the amplitude is tripled and the periodic time is doubled, then the new maximum velocity will be
A hollow metal sphere has a radius $r$. The potential difference between a point on its surface and at a point at a distance $3r$ from its centre is $V$. The electric intensity at the distance $3r$ from the centre of the sphere will be
The magnetic flux near the axis and inside an air core solenoid of length $60\text{ cm}$ carrying current $I$ is $1.57 \times 10^{-6}\text{ Wb}$. Its magnetic moment will be [$\mu_0 = 4\pi \times 10^{-7}$ SI units, and cross-sectional area is very small as compared to length of solenoid]
Two coherent sources 'P' and 'Q' produce interference at point 'A' on the screen, where there is a dark band which is formed between 4th and 5th bright band. Wavelength of light used is $6000\text{ \r{A}}$. The path difference PA and QA is
A condenser of capacity $C_1$ is charged to a potential $V_1$ and then disconnected. An uncharged capacitor of capacity $C_2$ is then connected in parallel with $C_1$. The resultant common potential $V_2$ is
In a step up transformer, which one of the following statements is correct?
The equation of a simple harmonic wave produced in a string under tension $0.4\text{ N}$ is given by $y = 4 \sin (3x + 60t)\text{ m}$. The mass per unit length of the string is
Magnetic moment of a revolving electron of charge $e$ and mass $m$ in terms of angular momentum $L$ of the electron is:
A proton and alpha particle are accelerated through the same potential difference. The ratio of the de-Broglie wavelength of proton to that of alpha particle will be (mass of alpha particle is four times mass of proton.)
A pendulum clock is running fast. To correct its time, we should
Two rods of same length and material are joined end to end. They transfer heat in 8 second. When they are joined in parallel they transfer same amount of heat in same conditions in time
The instantaneous value of an alternating current is given by $i = 50 \sin (100 \pi t)$. It will achieve a value of $25\text{ A}$ after a time interval of ($\sin 30^\circ = 0.5$)
A pipe closed at one end has length $0.8\text{ m}$. At its open end, a $0.5\text{ m}$ long uniform string is vibrating in its 2nd harmonic and it resonates with the fundamental frequency of the pipe. If the tension in the wire is $50\text{ N}$ and the speed of sound is $320\text{ m/s}$, the mass of the string is
Three rings each of mass $M$ and radius $R$ are arranged as shown in the figure. The moment of inertia of the system about the axis $YY'$ will be

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Photoemission from a metal surface takes place for frequencies $\nu_1$ and $\nu_2$ of incident rays ($\nu_1 > \nu_2$). The maximum kinetic energy of the photoelectrons emitted is in the ratio $1 : K$. The threshold frequency ($\nu_0$) of the metallic surface is
A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens material. Then its focal length will
The angle of banking $\theta$ for a meter gauge railway line is given by $\theta = \tan^{-1}\left(\frac{1}{20}\right)$. What is the elevation of the outer rail above the inner rail?
Three pure inductors each of inductance $6\text{ H}$ are connected as shown in the figure. Their equivalent inductance between the points 'P' and 'Q' is

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A body at rest falls through a height 'h' with velocity 'V'. If it has to fall down further for its velocity to become three times, the distance travelled in that interval is
A, B and C are three parallel conductors of equal lengths carrying currents $I$, $I$ and $2I$ respectively. Distance between A and B is $x$ and that between B and C is also $x$. $F_1$ is the force exerted by conductor B on A. $F_2$ is the force exerted by conductor C on A. Current $I$ in A and $I$ in B are in the same direction and current $2I$ in C is in the opposite direction. Then
The refractive index of glass is 1.5 and that of water is 1.33. The critical angle for a ray of light going from glass to water is
The north pole of a long horizontal bar magnet is being brought towards a closed circuit consisting of a coil. The direction of induced current produced in it is
A child is sitting on a swing which performs S.H.M. It has minimum and maximum heights from the ground as $0.75\text{ m}$ and $2\text{ m}$ respectively. Its maximum speed will be [$g = 10\text{ m/s}^2$]
If $E$ is the kinetic energy per mole of an ideal gas and $T$ is the absolute temperature, then the universal gas constant ($R$) is given as