JEE Main 2020 (Online) 6th September Evening Slot

In a series LR circuit, power of 400W is dissipated from a source of 250 V, 50 Hz. The power factor
of the circuit is 0.8. In order to bring the power factor to unity, a capacitor of value C is added in
series to the L and R. Taking the val...

Given the masses of various atomic particles
mp = 1.0072 u, mn = 1.0087 u, me = 0.000548 u,
\({m_{\overline v }}\) = 0, md = 2.0141 u, where p \(\equiv\) proton,
n \(\equiv\) neutron, e \(\equiv\) electron, \(\overline v\) $$ \equiv ...

The centre of mass of solid hemisphere of radius 8 cm is x from the centre of the flat surface. Then
value of x is __________.

Particle A of mass m1
moving with velocity \(\left( {\sqrt3\widehat i + \widehat j} \right)m{s^{ - 1}}\) collides with another particle B of mass m2
which is at rest initially. Let \(\overrightarrow {{V_1}}\)
and $$\overrightarrow {{V_2}...

A circuit to verify Ohm's law uses ammeter and voltmeter in series or parallel connected correctly
to the resistor. In the circuit :

In the figure shown, the current in the 10 V battery is close to :

Assuming the nitrogen molecule is moving with r.m.s. velocity at 400 K, the de-Broglie wavelength
of nitrogen molecule is close to :
(Given : nitrogen molecule weight : 4.64 \(\times\) 10–26 kg, Boltzman
constant: 1.38 \(\times\) 10–23...

For a plane electromagnetic wave, the magnetic field at a point x and time t is
\(\overrightarrow B \left( {x,t} \right)\) = $$\left[ {1.2 \times {{10}^{ - 7}}\sin \left( {0.5 \times {{10}^3}x + 1.5 \times {{10}^{11}}t} \right)\widehat k} \...

The output characteristics of a transistor is shown in the figure. When VCE is 10V and IC
= 4.0 mA,
then value of \(\beta\)ac
is __________.

Consider the force F on a charge 'q' due to a uniformly charged spherical shell of radius R carrying
charge Q distributed uniformly over it. Which one of the following statements is true for F, if 'q' is
placed at distance r from the centre...

Two identical electric point dipoles have dipole moments \({\overrightarrow p _1} = p\widehat i\) and \({\overrightarrow p _2} = - p\widehat i\) and are held on the x
axis at distance '\(a\)' from each other. When released, they move along...

A double convex lens has power P and same radii of curvature R of both the surfaces. The radius of
curvature of a surface of a plano-convex lens made of the same material with power 1.5 P is :

Two planets have masses M and 16 M and their radii are \(a\) and 2\(a\), respectively. The separation
between the centres of the planets is 10\(a\). A body of mass m is fired from the surface of the larger
planet towards the smaller planet ...

Three rods of identical cross-section and lengths are made of three different materials of thermal
conductivity K1
, K2
and K3
, respecrtively. They are joined together at their ends to make a long rod
(see figure). One end of the long rod...

An engine operates by taking a monoatomic ideal gas through the cycle shown in the figure. The
percentage efficiency of the engine is close to __________.

In a dilute gas at pressure P and temperature T, the mean time between successive collisions of a
molecule varies with T as :

A particle moving in the xy plane experiences a velocity dependent force
\(\overrightarrow F = k\left( {{v_y}\widehat i + {v_x}\widehat j} \right)\)
, where vx
and vy
are the x and y components of its velocity \(\overrightarrow v\)
. If ...

A charged particle going around in a circle can be considered to be a current loop. A particle of
mass m carrying charge q is moving in a plane with speed v under the influence of magnetic field \(\overrightarrow B\).
The magnetic moment o...

A square loop of side 2\(a\) and carrying current I is kept in xz plane with its centre at origin. A long
wire carrying the same current I is placed parallel to z-axis and passing through point (0, b, 0),
(b >> a). The magnitude of torque o...

When a car is at rest, its driver sees rain drops falling on it vertically. When driving the car with
speed v, he sees that rain drops are coming at an angle 60° from the horizontal. On further
increasing the speed of the car to (1 + $$\bet...

A fluid is flowing through a horizontal pipe of varying cross-section, with speed v ms–1 at a point
where the pressure is P pascal. At another point where pressure is \({P \over 2}\)
Pascal its speed is V ms–1. If
the density of the fluid ...

The linear mass density of a thin rod AB of length L varies from A to B as
\(\lambda \left( x \right) = {\lambda _0}\left( {1 + {x \over L}} \right)\), where
x is the distance from A. If M is the mass of the rod then its moment of inertia ...

When a particle of mass m is attached to a vertical spring of spring constant k and released, its
motion is described by y(t) = y0
sin2 \(\omega\)t, where 'y' is measured from the lower end of unstretched
spring. Then \(\omega\) is:

A student measuring the diameter of a pencil of circular cross-section with the help of a vernier
scale records the following four readings 5.50 mm, 5.55 mm, 5.45 mm, 5.65 mm. The average of
these four readings is 5.5375 mm and the standard...

A Young's double-slit experiment is performed using monochromatic light of wavelength \(\lambda\). The
intensity of light at a point on the screen, where the path difference is \(\lambda\), is K units. The intensity
of light at a point wh...