JEE Main 2021 Physics Paper: 16 Mar, Shift 1

An RC circuit as shown in the figure is driven by a AC source generating a square wave. The output wave pattern monitored by CRO would look close to:

A sinusoidal voltage of peak value 250 V is applied to a series LCR circuit, in which R = 8$\Omega$, L = 24 mH and C = 60 $\mu$F. The value of power dissipated at resonant condition is 'x' kW. The value of x to the nearest integer is ____________.

The first three spectral lines of H-atom in the Balmer series are

given $\lambda$1, $\lambda$2, $\lambda$3 considering the Bohr atomic model, the wave lengths of first and third spectral lines $\left(\frac{\lambda_1}{\lambda_3}\right)$ are related by a factor of approximately 'x' $\times$ 10$-$1.

The value of x, to the nearest integer, is _________.

For changing the capacitance of a given parallel plate capacitor, a dielectric material of dielectric constant K is used, which has the same area as the plates of the capacitor. The thickness of the dielectric slab is $\frac{3}{4}$ d, where 'd' is the separation between the plates of parallel plate capacitor. The new capacitance (C') in terms of original capacitance (C0) is given by the following relation:

A block of 200 g mass moves with a uniform speed in a horizontal circular groove, with vertical side walls of radius 20 cm. If the block takes 40 s to complete one round, the normal force by the side walls of the groove is:

A conducting wire of length 'l', area of cross-section A and electric resistivity $\rho$ is connected between the terminals of a battery. A potential difference V is developed between its ends, causing an electric current.

If the length of the wire of the same material is doubled and the area of cross-section is halved, the resultant current would be:

In the figure given, the electric current flowing through the 5 k$\Omega$ resistor is 'x' mA.

The value of x to the nearest integer is ____________.

The stopping potential in the context of photoelectric effect depends on the following property of incident electromagnetic radiation:

A conducting bar of length L is free to slide on two parallel conducting rails as shown in the figure

Two resistors R1 and R2 are connected across the ends of the rails. There is a uniform magnetic field $\vec{B}$ pointing into the page. An external agent pulls the bar to the left at a constant speed v. The correct statement about the directions of induced currents I1 and I2 flowing through R1 and R2 respectively is:

For an electromagnetic wave travelling in free space, the relation between average energy densities due to electric (Ue) and magnetic (Um) fields is:

A plane electromagnetic wave of frequency 500 MHz is travelling in vacuum along y-direction. At a particular point in space and time,

$\vec{B}$ = 8.0 $\times$ 10$-$8 $\hat{z}$T. The value of electric field at this point is:

(speed of light = 3 $\times$ 108 ms${}^{-1}$)

$\hat{x}\ \hat{y}\ \hat{z}$ are unit vectors along x, y and z directions.

The pressure acting on a submarine is 3 $\times$ 105 Pa at a certain depth. If the depth is doubled, the percentage increase in the pressure acting on the submarine would be:

(Assume that atmospheric pressure is 1 $\times$ 105 Pa and density of water is 103 kg m${}^{-3}$, g = 10 ms${}^{-2}$)

The maximum and minimum distances of a comet from the Sun are 1.6 $\times$ 1012 m and 8.0 $\times$ 1010 m respectively. If the speed of the comet at the nearest point is 6 $\times$ 104 ms${}^{-1}$, the speed at the farthest point is:

A block of mass m slides along a floor while a force of magnitude F is applied to it at an angle $\theta$ as shown in figure. The coefficient of kinetic friction is $\mu$k. Then, the block's acceleration 'a' is given by: (g is acceleration due to gravity)

A bar magnet of length 14 cm is placed in the magnetic meridian with its north pole pointing towards the geographic north pole. A neutral point is obtained at a distance of 18 cm from the center of the magnet. If BH = 0.4 G, the magnetic moment of the magnet is: (1G = 10$-$4 T)

The velocity-displacement graph describing the motion of bicycle is shown in the figure.

The acceleration-displacement graph of the bicycle's motion is best described by:

Time period of a simple pendulum is T inside a lift when the lift is stationary. If the lift moves upwards with an acceleration g/2, the time period of pendulum will be:

The angle of deviation through a prism is minimum when

(A) Incident ray and emergent ray are symmetric to the prism.

(B) The refracted ray inside the prism becomes parallel to its base

(C) Angle of incidence is equal to that of the angle of emergence

(D) When angle of emergence is double the angle of incidence

Choose the correct answer from the options given below:

Four equal masses, m each are placed at the corners of a square of length (l) as shown in the figure. The moment of inertia of the system about an axis passing through A and parallel to DB would be:

Consider a 20 kg uniform circular disk of radius 0.2 m. It is pin supported at its center and is at rest initially. The disk is acted upon by a constant force F = 20 N through a massless string wrapped around its periphery as shown in the figure.

Suppose the disk makes n number of revolutions to attain an angular speed of 50 rad s${}^{-1}$. The value of n, to the nearest integer, is __________.

[Given: In one complete revolution, the disk rotates by 6.28 rad]

Consider a frame that is made up of two thin massless rods AB and AC as shown in the figure. A vertical force $\vec{P}$of magnitude 100 N is applied at point A of the frame.

Suppose the force $\vec{P}$is resolved parallel to the arms AB and AC of the frame.

The magnitude of the resolved component along the arm AC is xN.

The value of x, to the nearest integer, is ___________.

[Given: sin(35$^\circ$) = 0.573, cos(35$^\circ$) = 0.819

sin(110$^\circ$) = 0.939, cos(110$^\circ$) = $-$ 0.342]

In the logic circuit shown in the figure, if input A and B are 0 and 1 respectively, the output at Y would be 'x'.

The value of x is ____________.

The value of power dissipated across the zener diode (Vz = 15V) connected in the circuit as shown in the figure is x $\times$ 10$-$1 watt.

The value of x, to the nearest integer, is __________.

The volume V of an enclosure contains a mixture of three gases, 16 g of oxygen, 28 g of nitrogen and 44 g of carbon dioxide at absolute temperature T. Consider R as universal gas constant. The pressure of the mixture of gases is:

In thermodynamics, heat and work are:

The resistance R = $\frac{V}{I}$, where V = (50 $\pm$ 2)V and I = (20 $\pm$ 0.2)A. The percentage error in R is 'x'%. The value of 'x' to the nearest integer is _________.

One main scale division of a vernier callipers is 'a' cm and nth division of the vernier scale coincide with (n $-$ 1)th division of the main scale. The least count of the callipers in mm is:

A fringe width of 6 mm was produced for two slits separated by 1 mm apart. The screen is placed 10 m away. The wavelength of light used is 'x' nm. The value of 'x' to the nearest integer is ____________.