NEET 2020 Physics Paper: Phase 2

A light bulb and an inductor coil are connected to an ac source through a key as shown in the figure below. The key is closed and after sometime an iron rod is inserted into the interior of the inductor. The glow of the light bulb

The total energy of an electron in the $n$th stationary orbit of the hydrogen atom can be obtained by

A parallel plate capacitor having cross-sectional area $A$ and separation $d$ has air in between the plates. Now an insulating slab of same area but thickness $d/2$ is inserted between the plates as shown in figure having dielectric constant $K(=4)$. The ratio of new capacitance to its original capacitance will be,

Three identical spheres, each of mass $M$, are placed at the corners of a right angle triangle with mutually perpendicular sides equal to 2 m (see figure). Taking the point of intersection of the two mutually perpendicular sides as the origin, find the position vector of centre of mass.

The equivalent resistance between $A$ and $B$ for the mesh shown in the figure is

For the circuit given below, the Kirchoff's loop rule for the loop $BCDEB$ is given by the equation

For the circuit shown in the figure, the current $I$ will be

Two solid conductors are made up of same material, have same length and same resistance. One of them has a circular cross section of area $A_1$ and the other one has a square cross section of area $A_2$. The ratio $A_1/A_2$ is

The wave nature of electrons was experimentally verified by,

The de Broglie wavelength of an electron moving with kinetic energy of 144 eV is nearly

The magnetic flux linked with a coil (in Wb) is given by the equation

$\phi = 5t^{2} + 3t + 16$

The magnitude of induced emf in the coil at the fourth second will be

A wheel with 20 metallic spokes each $1\text{ m}$ long is rotated with a speed of $120\text{ rpm}$ in a plane perpendicular to a magnetic field of $0.4\text{ G}$. The induced emf between the axle and rim of the wheel will be $(1\text{ G} = 10^{-4}\text{ T})$

The E.M. wave with shortest wavelength among the following is,

The magnetic field in a plane electromagnetic wave is given by,

$B_y = 2\times 10^{-7}\sin(\pi\times 10^{3}x + 3\pi\times 10^{11}t)\text{ T}$

Calculate the wavelength.

The acceleration of an electron due to the mutual attraction between the electron and a proton when they are 1.6 Å apart is,

$(m_e \simeq 9 \times 10^{-31}\text{ kg},\ e = 1.6 \times 10^{-19}\text{ C})$

(Take $\frac{1}{4\pi\epsilon_0} = 9 \times 10^{9}\text{ N m}^2\text{ C}^{-2}$)

The electric field at a point on the equatorial plane at a distance $r$ from the centre of a dipole having dipole moment $\vec{p}$ is given by,

($r \gg$ separation of two charges forming the dipole, $\varepsilon_0$ - permittivity of free space)

The variation of electrostatic potential with radial distance $r$ from the centre of a positively charged metallic thin shell of radius $R$ is given by the graph

A barometer is constructed using a liquid (density = $760\text{ kg/m}^{3}$). What would be the height of the liquid column, when a mercury barometer reads 76 cm?

(density of mercury = $13600\text{ kg/m}^{3}$)

What is the depth at which the value of acceleration due to gravity becomes $1/n$ times the value that at the surface of earth? (radius of earth $= R$)

Three stars $A, B, C$ have surface temperatures $T_{A}, T_{B}, T_{C}$ respectively. Star $A$ appears bluish, star $B$ appears reddish and star $C$ yellowish. Hence,

The mean free path $\ell$ for a gas molecule depends upon diameter, $d$ of the molecule as

A point mass '$m$' is moved in a vertical circle of radius '$r$' with the help of a string. The velocity of the mass is $\sqrt{7gr}$ at the lowest point. The tension in the string at the lowest point is

Calculate the acceleration of the block and trolly system shown in the figure. The coefficient of kinetic friction between the trolly and the surface is 0.05. ($g = 10\text{ m/s}^{2}$, mass of the string is negligible and no other friction exists).

A person sitting in the ground floor of a building notices through the window, of height 1.5 m, a ball dropped from the roof of the building crosses the window in 0.1 s. What is the velocity of the ball when it is at the topmost point of the window? ($g = 10\text{ m/s}^2$)

A wire of length $L$ metre carrying a current of $I$ ampere is bent in the form of a circle. Its magnetic moment is

The half life of a radioactive sample undergoing $\alpha$-decay is $1.4 \times 10^{17}\text{ s}$. If the number of nuclei in the sample is $2.0 \times 10^{21}$, the activity of the sample is nearly

What happens to the mass number and atomic number of an element when it emits $\gamma$-radiation?

Identify the function which represents a periodic motion.

An object is placed on the principal axis of a concave mirror at a distance of $1.5f$ ($f$ is the focal length). The image will be at,

The power of a biconvex lens is 10 dioptre and the radius of curvature of each surface is 10 cm. Then the refractive index of the material of the lens is,

A plano-convex lens of unknown material and unknown focal length is given. With the help of a spherometer we can measure the,

If the critical angle for total internal reflection from a medium to vacuum is $45^\circ$, then velocity of light in the medium is,

The angular speed of the wheel of a vehicle is increased from 360 rpm to 1200 rpm in 14 second. Its angular acceleration is,

An intrinsic semiconductor is converted into $n$-type extrinsic semiconductor by doping it with

A n-p-n transistor is connected in common emitter configuration (see figure) in which collector voltage drop across load resistance $(800\ \Omega)$ connected to the collector circuit is $0.8\text{ V}$. The collector current is

Which of the following gate is called universal gate?

Out of the following which one is a forward biased diode?

A liquid does not wet the solid surface if angle of contact is

An ideal gas equation can be written as

$P = \frac{\rho RT}{M_0}$

where $\rho$ and $M_0$ are respectively,

The efficiency of a Carnot engine depends upon

The $P\text{-}V$ diagram for an ideal gas in a piston cylinder assembly undergoing a thermodynamic process is shown in the figure. The process is

Time intervals measured by a clock give the following readings:

1.25 s, 1.24 s, 1.27 s, 1.21 s and 1.28 s

What is the percentage relative error of the observations?

The angle of 1′ (minute of arc) in radian is nearly equal to

The length of the string of a musical instrument is 90 cm and has a fundamental frequency of 120 Hz. Where should it be pressed to produce fundamental frequency of 180 Hz?

Two coherent sources of light interfere and produce fringe pattern on a screen. For central maximum, the phase difference between the two waves will be,