JEE Main 2020 (Online) 6th September Morning Slot

An AC circuit has R= 100 \(\Omega\), C = 2 \(\mu\)F and L = 80 mH, connected in series. The quality factor of the
circuit is :

You are given that Mass of \({}_3^7Li\) = 7.0160u,
Mass of \({}_2^4He\) = 4.0026u
and Mass of \({}_1^1H\) = 1.0079u.
When 20 g of \({}_3^7Li\) is converted into \({}_2^4He\) by proton capture, the energy liberated, (in kWh), is :
[Mass of n...

For the given input voltage waveform Vin(t), the output voltage waveform V0(t), across the
capacitor is correctly depicted by :

Two bodies of the same mass are moving with the same speed, but in different directions in a
plane. They have a completely inelastic collision and move together thereafter with a final speed
which is half of their initial speed. The angle b...

A clock has a continuously moving second's hand of 0.1 m length. The average acceleration of the
tip of the hand (in units of ms–2) is of the order of :

An electron, a doubly ionized helium ion (He++) and a proton are having the same kinetic energy.
The relation between their respective de-Broglie wavelengths \(\lambda\)e, \(\lambda\)He++ and \(\lambda\)p is :

A part of a complete circuit is shown in the figure. At some instant, the value of current I is 1A and
it is decreasing at a rate of 102 A s–1. The value of the potential difference VP
– VQ
, (in volts) at
that instant, is _________.

Suppose that intensity of a laser is \({{315} \over \pi }\) W/m2. The rms electric field, in units of V/m associated
with this source is close to the nearest integer is __________.
\(\in\)0 = 8.86 × 10–12 C2 Nm–2; c = 3 × 108 ms–1)

Identify the correct output signal Y in the given combination of gates (as shown) for the given
inputs A and B.

Charges Q1
and Q2
are at points A and B of a right angle triangle OAB (see figure). The resultant
electric field at point O is perpendicular to the hypotenuse, then \({{{Q_1}} \over {{Q_2}}}\)
is proportional to :

A point like object is placed at a distance of 1 m in front of a convex lens of focal length 0.5 m. A
plane mirror is placed at a distance of 2 m behind the lens. The position and nature of the final
image formed by the system is :

A satellite is in an elliptical orbit around a planet P. It is observed that the velocity of the satellite
when it is farthest from the planet is 6 times less than that when it is closest to the planet. The
ratio of distances between the sa...

Initially a gas of diatomic molecules is contained in a cylinder of volume V1
at a pressure P1
and
temperature 250 K. Assuming that 25% of the molecules get dissociated causing a change in
number of moles. The pressure of the resulting ga...

Molecules of an ideal gas are known to have three translational degrees of freedom and two
rotational degrees of freedom.The gas is maintained at a temperature of T. The total internal
energy, U of a mole of this gas, and the value of $$\ga...

An insect is at the bottom of a hemispherical ditch of radius 1 m. It crawls up the ditch but starts
slipping after it is at height h from the bottom. If the coefficient of friction between the ground and
the insect is 0.75, then h is :
(g...

An electron is moving along +x direction with a velocity of 6 \(\times\) 106
ms–1. It enters a region of uniform
electric field of 300 V/cm pointing along +y direction. The magnitude and direction of the magnetic
field set up in this reg...

A particle of charge q and mass m is moving with a velocity \(- v\widehat i\) (v \(\ne\) 0) towards a large screen
placed in the Y - Z plane at a distance d. If there is a magnetic field \(\overrightarrow B = {B_0}\widehat k\)
, the max...

An object of mass m is suspended at the end of a massless wire of length L and area of crosssection A. Young modulus of the material of the wire is Y. If the mass is pulled down slightly its
frequency of oscillation along the vertical direc...

Four point masses, each of mass m, are fixed at the corners of a square of side \(l\). The square is
rotating with angular frequency \(\omega\), about an axis passing through one of the corners of the square
and parallel to its diagonal, a...

Shown in the figure is a hollow icecream cone (it is open at the top). If its mass is M, radius of its
top, R and height, H, then its moment of inertia about its axis is :

The density of a solid metal sphere is determined by measuring its mass and its diameter. The
maximum error in the density of the sphere is \(\left( {{x \over {100}}} \right)\) %. If the relative errors in measuring the mass
and the diamet...

A screw gauge has 50 divisions on its circular scale. The circular scale is 4 units ahead of the
pitch scale marking, prior to use. Upon one complete rotation of the circular scale, a displacement of 0.5mm is noticed on the pitch scale. The...

In the figure below, P and Q are two equally intense coherent sources emitting radiation of
wavelength 20 m. The separation between P and Q is 5 m and the phase of P is ahead of that of Q
by 90o. A, B and C are three distinct points of obse...

A sound source S is moving along a straight track with speed v, and is emitting, sound of frequency
v0
(see figure). An observer is standing at a finite distance, at the point O, from the track. The
time variation of frequency heard by the...

If the potential energy between two molecules is given by
U = \(- {A \over {{r^6}}} + {B \over {{r^{12}}}}\),
then at equilibrium,
separation between molecules, and the potential energy are :