JEE Main 2020 (Online) 4th September Morning Slot

Blocks of masses m, 2m, 4m and 8m are arranged in a line on a frictionless floor. Another block of
mass m, moving with speed v along the same line (see figure) collides with mass m in perfectly
inelastic manner. All the subsequent collision...

A battery of 3.0 V is connected to a resistor dissipating 0.5 W of power. If the terminal voltage of the battery is 2.5 V, the power dissipated within the internal resistance is :

Particle A of mass mA = \({m \over 2}\) moving along the x-axis with velocity v0 collides elastically with another particle B at rest having mass mB = \({m \over 3}\). If both particles move along the x-axis after the collision, the change ...

Given figure shows few data points in a phot electric effect experiment for a certain metal. The
minimum energy for ejection of electron from its surface is: (Plancks constant h = 6.62 × 10–34 J.s)

A small bar magnet is moved through a coil at constant speed from one end to the other. Which of the following series of observations will be seen on the galvanometer G attached across the coil?

Three positions shown describe : (a) the mag...

Choose the correct option relating wave lengths of different parts of electromagnetic wave spectrum:

Take the breakdown voltage of the zener diode used in the given circuit as 6V. For the input voltage shown in figure below, the time variation of the output voltage is: (Graphs drawn are schematic and not to scale)

Two charged thin infinite plane sheets of uniform surface charge density \({\sigma _ + }\) and \({\sigma _ - }\), where |\({\sigma _ + }\)| > |\({\sigma _ - }\)|, intersect at right angle. Which of the following best represents the
electri...

A two point charges 4q and -q are fixed
on the x-axis at x = \(- {d \over 2}\)
and x = \({d \over 2}\)
respectively. If a third point charge 'q' is taken from the origin to x = d along the semicircle as shown in the figure, the energy of t...

In a compound microscope, the magnified virtual image is formed at a distance of 25 cm from the
eye-piece. The focal length of its objective lens is 1 cm. If the magnification is 100 and the tube
length of the microscope is 20 cm, then the ...

On the x-axis and at a distance x from the origin, the gravitational field due a mass distribution is
given by \({{Ax} \over {{{\left( {{x^2} + {a^2}} \right)}^{3/2}}}}\) in the x-direction. The magnitude of gravitational potential on the x...

The specific heat of water = 4200 J kg-1K-1 and the latent heat of ice = 3.4 \(\times\) 105 J kg–1. 100 grams of ice at 0oC is placed in 200 g of water at 25oC. The amount of ice that will melt as the temperature of water reaches 0oC is c...

Match the \({{{C_P}} \over {{C_V}}}\) ratio for ideal gases with different type of molecules :

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A closed vessel contains 0.1 mole of a monoatomic ideal gas at 200 K. If 0.05 mole of the same gas
at 400 K is added to it, the final equilibrium temperature (in K) of the gas in the vessel will be close
to _______.

A small bar magnet placed with its axis at 30o with an external field of 0.06 T experiences a torque of 0.018 Nm. The minimum work required to rotate it from its stable to unstable equilibrium position is :

A wire A, bent in the shape of an arc of a circle, carrying a current of 2 A and having radius 2 cm and another wire B, also bent in the shape of arc of a circle, carrying a current of 3 A and having radius of 4 cm, are placed as shown in t...

Starting from the origin at time t = 0, with initial velocity 5\(\widehat j\) ms-1 , a particle moves in the x-y plane
with a constant acceleration of \(\left( {10\widehat i + 4\widehat j} \right)\) ms-2. At time t, its coordinates are (20 ...

A Tennis ball is released from a height h and after freely falling on a wooden floor
it rebounds and reaches height \({h \over 2}\). The
velocity versus height of the ball during its motion may be represented graphically by : (graph are dra...

A air bubble of radius 1 cm in water has an upward acceleration 9.8 cm s–2. The density of water is
1 gm cm–3 and water offers negligible drag force on the bubble. The mass of the bubble is (g = 980
cm/s2).

A circular disc of mass M and radius R is rotating about its axis with angular speed \({\omega _1}\)
. If another
stationary disc having radius \({R \over 2}\) and same mass M is droped co-axially on to the rotating disc.
Gradually both dis...

Dimensional formula for thermal conductivity is (here K denotes the temperature):

A beam of plane polarised light of large cross-sectional area and uniform intensity of 3.3 Wm-2 falls normally on a polariser (cross sectional area 3 \(\times\) 10-4 m2) which rotates about its axis with an angular speed of 31.4 rad/s. Th...

For a transverse wave travelling along a straight line, the distance between two peaks (crests) is 5 m, while the distance between one crest and one trough is 1.5 m. The possible wavelengths (in m) of the are :