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JEE Main 2021 Physics Paper: 18 Mar, Shift 1

Questions
28
Chapters
23

These are the 28 physics questions of JEE Main 2021 (18 Mar, Shift 1) that are in the Physics Circle question bank, arranged chapter by chapter. Tap an option to check your answer; every question links to its full solution.

Alternating Current 2 questions · chapter PYQs

Q1JEE Main 2021 · 18 MAR · SHIFT 1Easy

AC Basics: Peak, RMS & Average Values

An AC source rated 220 V, 50 Hz is connected to a resistor. The time taken by the current to change from its maximum to the rms value is:

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Q2JEE Main 2021 · 18 MAR · SHIFT 1Easy

Resonance, Bandwidth & Q Factor

In a series LCR resonance circuit, if we change the resistance only, from a lower to higher value:

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Atomic Structure 1 questions · chapter PYQs

Q3JEE Main 2021 · 18 MAR · SHIFT 1Medium

Bohr Model: Orbits, Speed & Angular Momentum

Imagine that the electron in a hydrogen atom is replaced by a muon (μ\mu). The mass of muon particle is 207 times that of an electron and charge is equal to the charge of an electron. The ionization potential of this hydrogen atom will be:

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Capacitors 2 questions · chapter PYQs

Q4JEE Main 2021 · 18 MAR · SHIFT 1Medium

Capacitors in DC Circuits & RC

The circuit shown in the figure consists of a charged capacitor of capacity 3 μ\muF and a charge of 30 μ\muC. At time t = 0, when the key is closed, the value of current flowing through the 5 MΩ\Omega resistor is 'x' μ\mu-A. The value of 'x' to the nearest integer is ___________.

Figure

Numerical answer type. Work it out, then open the answer.

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Q5JEE Main 2021 · 18 MAR · SHIFT 1Easy

Dielectrics

A parallel plate capacitor has plate area 100 m2 and plate separation of 10 m. The space between the plates is filled up to a thickness 5 m with a material of dielectric constant of 10. The resultant capacitance of the system is 'x' pF.

The value of ε\varepsilon0 = 8.85 ×\times 10−-12 F.m−1{}^{-1}.

The value of 'x' to the nearest integer is _____________.

Numerical answer type. Work it out, then open the answer.

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Current Electricity 1 questions · chapter PYQs

Q6JEE Main 2021 · 18 MAR · SHIFT 1Medium

Kirchhoff's Laws & Measuring Instruments

The voltage across the 10Ω\Omega resistor in the given circuit is x volt.

Figure

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

Numerical answer type. Work it out, then open the answer.

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Dual Nature of Radiation and Matter 1 questions · chapter PYQs

Q7JEE Main 2021 · 18 MAR · SHIFT 1Medium

Matter Waves: de Broglie Wavelength

A particle is travelling 4 time as fast as an electron. Assuming the ratio of de-Broglie wavelength of a particle to that of electron is 2: 1, the mass of the particle is:

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Electromagnetic Waves 1 questions · chapter PYQs

Q8JEE Main 2021 · 18 MAR · SHIFT 1Easy

Nature of EM Waves & Wave Equation

A plane electromagnetic wave of frequency 100 MHz is travelling in vacuum along the x-direction. At a particular point in space and time, B⃗=2.0×10−8k^ T\vec{B} = 2.0\times 10^{-8}\hat{k}\text{ T}. (where, k^\hat{k} is unit vector along z-direction) What is E⃗\vec{E} at this point?

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Electrostatics 1 questions · chapter PYQs

Q9JEE Main 2021 · 18 MAR · SHIFT 1Medium

Motion of Charges in an Electric Field

An oil drop of radius 2 mm with a density 3g cm−3{}^{-3} is held stationary under a constant electric field 3.55 ×\times 105 V m−1{}^{-1} in the Millikan's oil drop experiment. What is the number of excess electrons that the oil drop will possess? (consider g = 9.81 m/s2)

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Gravitation 1 questions · chapter PYQs

Q10JEE Main 2021 · 18 MAR · SHIFT 1Easy

Satellites - Orbital Velocity & Period

The time period of a satellite in a circular orbit of radius R is T. The period of another satellite in a circular orbit of radius 9R is:

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Kinetic Theory of Gases 1 questions · chapter PYQs

Q11JEE Main 2021 · 18 MAR · SHIFT 1Easy

Law of Equipartition of Energy

What will be the average value of energy along one degree of freedom for an ideal gas in thermal equilibrium at a temperature T? (kB is Boltzmann constant)

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Laws of Motion 1 questions · chapter PYQs

Q12JEE Main 2021 · 18 MAR · SHIFT 1Easy

Inertia, First & Second Laws

A bullet of mass 0.1 kg is fired on a wooden block to pierce through it, but it stops after moving a distance of 50 cm into it. If the velocity of bullet before hitting the wood is 10 m/s and it slows down with uniform deceleration, then the magnitude of effective retarding force on the bullet is 'x' N. The value of 'x' to the nearest integer is __________.

Numerical answer type. Work it out, then open the answer.

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Mechanical Properties of Solids 1 questions · chapter PYQs

Q13JEE Main 2021 · 18 MAR · SHIFT 1Medium

Young's Modulus & Elongation

Two separate wires A and B are stretched by 2 mm and 4 mm respectively, when they are subjected to a force of 2 N. Assume that both the wires are made up of same material and the radius of wire B is 4 times that of the radius of wire A. The length of the wires A and B are in the ratio of a: b. Then a/b can be expressed as 1/x where x is _________.

Numerical answer type. Work it out, then open the answer.

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Motion in One Dimension 1 questions · chapter PYQs

Moving Charges and Magnetism 2 questions · chapter PYQs

Q15JEE Main 2021 · 18 MAR · SHIFT 1Difficult

Ampere's Law, Cylinders, Solenoid & Toroid

Four identical long solenoids A, B, C and D are connected to each other as shown in the figure. If the magnetic field at the center of A is 3T, the field at the center of C would be: (Assume that the magnetic field is confined with in the volume of respective solenoid).

Figure

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Q16JEE Main 2021 · 18 MAR · SHIFT 1Easy

Force on Current-Carrying Conductors

A loop of flexible wire of irregular shape carrying current is placed in an external magnetic field. Identify the effect of the field on the wire.

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Nuclear Physics 1 questions · chapter PYQs

Q17JEE Main 2021 · 18 MAR · SHIFT 1Easy

Law of Radioactive Decay

A radioactive sample disintegrates via two independent decay processes having half lives T1/2(1)T_{1/2}^{(1)} and T1/2(2)T_{1/2}^{(2)} respectively. The effective half-life T1/2 of the nuclei is:

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Oscillations 1 questions · chapter PYQs

Q18JEE Main 2021 · 18 MAR · SHIFT 1Easy

Periodic Motion & SHM Basics

A particle performs simple harmonic motion with a period of 2 second. The time taken by the particle to cover a displacement equal to half of its amplitude from the mean position is 1a\frac{1}{a}s. The value of 'a' to the nearest integer is _________.

Numerical answer type. Work it out, then open the answer.

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Projectile Motion 1 questions · chapter PYQs

Q19JEE Main 2021 · 18 MAR · SHIFT 1Medium

Relative Velocity in Two Dimensions

A person is swimming with a speed of 10 m/s at an angle of 120∘^\circ with the flow and reaches to a point directly opposite on the other side of the river. The speed of the flow is 'x' m/s. The value of 'x' to the nearest integer is __________.

Numerical answer type. Work it out, then open the answer.

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Ray Optics 1 questions · chapter PYQs

Q20JEE Main 2021 · 18 MAR · SHIFT 1Easy

Optical Instruments & the Eye

Your friend is having eye sight problem. She is not able to see clearly a distant uniform window mesh and it appears to her as non-uniform and distorted. The doctor diagnosed the problem as:

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Rotational Motion 1 questions · chapter PYQs

Q21JEE Main 2021 · 18 MAR · SHIFT 1Medium

Angular Momentum & its Conservation

A thin circular ring of mass M and radius r is rotating about its axis with an angular speed ω\omega. Two particles having mass m each are now attached at diametrically opposite points. The angular speed of the ring will become:

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Semiconductor Electronics 1 questions · chapter PYQs

Q22JEE Main 2021 · 18 MAR · SHIFT 1Medium

Junction Transistor

An npn transistor operates as a common emitter amplifier with a power gain of 106. The input circuit resistance is 100Ω\Omega and the output load resistance is 10 KΩ\Omega. The common emitter current gain 'β\beta' will be ________. (Round off to the Nearest Integer).

Numerical answer type. Work it out, then open the answer.

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Thermodynamics 1 questions · chapter PYQs

Q23JEE Main 2021 · 18 MAR · SHIFT 1Medium

P-V Diagrams & Cyclic Processes

The P-V diagram of a diatomic ideal gas system going under cyclic process as shown in figure. The work done during an adiabatic process CD is (use γ\gamma = 1.4):

Figure

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Units, Dimensions and Measurement 2 questions · chapter PYQs

Q24JEE Main 2021 · 18 MAR · SHIFT 1Difficult

Errors in Measurement

In the experiment of Ohm's law, a potential difference of 5.0 V is applied across the end of a conductor of length 10.0 cm and diameter of 5.00 mm. The measured current in the conductor is 2.00 A. The maximum permissible percentage error in the resistivity of the conductor is:

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Q25JEE Main 2021 · 18 MAR · SHIFT 1Difficult

Errors in Measurement

The time period of a simple pendulum is given by T=2πlgT = 2\pi\sqrt{\frac{l}{g}}. The measured value of the length of pendulum is 10 cm known to a 1mm accuracy. The time for 200 oscillations of the pendulum is found to be 100 second using a clock of 1s resolution. The percentage accuracy in the determination of 'g' using this pendulum is 'x'. The value of 'x' to be nearest integer is :-

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Wave Optics 1 questions · chapter PYQs

Q26JEE Main 2021 · 18 MAR · SHIFT 1Easy

YDSE: Fringe Width & Fringe Positions

In Young's double slit arrangement, slits are separated by a gap of 0.5 mm, and the screen is placed at a distance of 0.5 m from them. The distance between the first and the third bright fringe formed when the slits are illuminated by a monochromatic light of 5890 A˚\text{Å} is :-

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Work, Energy and Power 2 questions · chapter PYQs

Q27JEE Main 2021 · 18 MAR · SHIFT 1Easy

Conservation of Energy

As shown in the figure, a particle of mass 10 kg is placed at a point A. When the particle is slightly displaced to its right, it starts moving and reaches the point B. The speed of the particle at B is x m/s. (Take g = 10 m/s2)

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

Figure

Numerical answer type. Work it out, then open the answer.

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Q28JEE Main 2021 · 18 MAR · SHIFT 1Easy

Power

A constant power delivering machine has towed a box, which was initially at rest, along a horizontal straight line. The distance moved by the box in time 't' is proportional to :-

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