MHT CET 2021 Physics Paper: 21 Sep, Shift 2

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 $(\sin 30^\circ = 0.5)$

In a step up transformer, which one of the following statements is correct?

Three pure inductors each of inductance 6H are connected as shown in the figure. Their equivalent inductance between the points 'P' and 'Q' is

The inductive reactance of a coil is R$\Omega$. If the inductance of a coil is doubled and frequency of a.c. supply is also doubled then the new inductive reactance will be

In LCR series resonant circuit, at resonance, voltage across 'L' and 'C' will cancel each other because they are

Ratio centripetal acceleration for an electron revolving in 3rd and 5th Bohr orbit of hydrogen atom is

A condenser of capacity '$C_1$' is charged to potential '$V_1$ ' and then disconnected. Uncharged capacitor of capacity '$C_2$' is connected in parallel with '$C_1$'. The resultant potential '$V_2$' is

Two identical parallel plate air capacitors are connected in series to a battery of emf '$V$'. If one of the capacitor is inserted in liquid of dielectric constant '$K$' then, potential difference of the other capacitor will become

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?

A current through 1 $\Omega$ resistance in the following circuit is

A moving coil galvanometer is converted into an ammeter, reading upto $0.04\text{ A}$ by connecting a shunt of resistance '$3r$' across it and then into an ammeter reading upto $0.08\text{ A}$, when a shunt of resistance '$r$' is connected across it. What is the maximum current which can be sent through this galvanometer if no shunt is used?

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.)

The wave number of the last line of the Balmer series in the hydrogen spectrum will be $($ Rydberg's cons $\text{tant}, R = \frac{10^{7}}{\text{m}})$

Photoemission from metal surface takes place for frequencies '$v_1$ ' and '$v_2$' of incident rays $(v_1 > v_2)$. Maximum kinetic energy of photoelectrons emitted is in the ratio $1 : K$. The threshold frequency of metallic surface is

When a piece of polythene is rubbed with wool, a negative charge of $4 \times 10^{-7}\text{ C}$ is developed on the polythene. The number of electrons transferred from wool to polythene is $[e = 1.6 \times 10^{-19}\text{ C}]$

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:

For a body of mass '$m$', the acceleration due to gravity at a distance '$R$' from the surface of the earth is $\left(\frac{g}{4}\right)$. Its value at a distance $\left(\frac{R}{2}\right)$ from the surface of the earth is ( $R =$ radius of the earth, $g =$ acceleration due to gravity)

The ratio of energy required to raise a satellite of mass '$m$' to height '$h$' above the earth's surface to that required to put it into the orbit at same height is [ $R =$ radius of earth]

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

What is the ratio of the velocity of sound in hydrogen $\left(\gamma = \frac{7}{5}\right)$ to that in helium $\left(\gamma = \frac{5}{3}\right)$ at the same temperature? (Molecular weight of hydrogen and helium is 2 and 4 respectively.)

Equal volumes of two gases are kept in different containers having densities in the ratio 1: 16. They exert equal pressures on the wall of their respective containers. Then the ratio of their r.m.s. velocities is

If '$E$' is the kinetic energy per mole of an ideal gas and '$T$' is the absolute temperature, then the universal gas constant is given as

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

Magnetic moment of revolving electron of charge (e) and mass (m) in terms of angular momentum (L) of electron is:

The magnetic flux near the axis and inside the 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 unit and cross-sectional area is very small as compared to length of solenoid.]

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 same direction and current $2I$ in $C$ is in opposite direction. Then

A pendulum clock is running fast. To correct its time, we should

A child is sitting on a swing which performs S.H.M. It has minimum and maximum heights from ground $0.75\text{ m}$ and $2\text{ m}$ respectively. Its maximum speed will be $\left[g = 10\,\frac{\text{m}}{\text{s}^{2}}\right]$

A particle is performing S.H.M. with maximum velocity '$v$'. If the amplitude is tripled and periodic time is doubled then maximum velocity will be

A convex lens is dipped in a liquid whose refractive index is equal to refractive index of lens material. Then its focal length will

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

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

A particle performs rotational motion with an angular momentum 'L'. If frequency of rotation is doubled and its kinetic energy becomes one fourth, the angular momentum becomes.

Combination of NAND gates is shown in the figure. It is equivalent to

In an ideal junction diode, the current flowing through PQ is

LED is manufactured using zinc selenide then it emits.

In a capillary tube having area of cross-section A, water rises to a height 'h'. If cross-sectional area is reduced to $\frac{A}{9}$, the rise of water in the capillary tube is

Water rises upto a height $10\text{ cm}$ in a capillary tube. It will rise to a height which is much more than $10\text{ cm}$ in a very long capillary tube if the apparatus is kept.

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

Under isothermal conditions, two soap bubbles of radii '$r_1$' and '$r_2$ ' combine to form a single soap bubble of radius '$R$'. The surface tension of soap is ( $P =$ outside pressure)

In thermodynamics, for an isochoric process, which one of the following statement is INCORRECT?

A pipe closed at one end has length $0.8\text{ m}$. At its open end $0.5\text{ m}$ long uniform string is vibrating in its $2$nd 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

Equation of two simple harmonic waves are given by $Y_1 = 2\sin 8\pi\left(\frac{t}{0.2} - \frac{x}{2}\right)\text{m}$ and $Y_2 = 4\sin 8\pi\left(\frac{t}{0.16} - \frac{x}{1.6}\right)\text{m}$ then both waves have

The equation of simple harmonic wave produced in the 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

Two coherent sources of wavelength '$\lambda$' produce steady interference pattern. The path difference corresponding to 10$^{th}$ order maximum will be

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 $\text{Å}$. The path difference PA and QA is

In Young's experiment, fringes are obtained on a screen placed at a distance $75\text{ cm}$ from the slits. When the separation between two narrow slits is doubled, then the fringe width is decreased. In order to obtain the initial fringe width, the screen should be moved through.

Three bodies P, Q and R have masses 'm' kg, '2m' kg and '3m' kg respectively. If all the bodies have equal kinetic energy, then greater momentum will be for body/bodies.