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JEE Mains 2020 physics questions with solutions
Browse JEE Mains 2020 Physics questions with solutions. Useful for JEE, NEET, and school exam revision.
Showing 1–10 of 54 questions
- MCQmediumGeometrical optics
If we need a magnification of 375 from a compound microscope of tube length 150 mm and an objective of focal length 5 mm, the focal length of the eye-piece, should be close to:
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JEE Mains 2020
Open question & full solution → - IntegermediumNewtons law of motion and Friction
A block starts from B on an incline. Section BC is smooth and CA is rough. The block comes to rest exactly at A. If BC = 2AC and μ = k tanθ, find k.
JEE Mains 2020
Open question & full solution → - NumericmediumRotational Motion
A uniform cubical box of side a rests on a rough floor and is to be moved by applying the minimum possible force F at a point b above its centre of mass. If µ = 0.4, find the maximum value of 100b/a for which the box does not topple before moving.
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Open question & full solution → - MCQmediumElectromagnetic Induction
A uniform magnetic field B exists in a direction perpendicular to the plane of a square loop made of a metal wire. The wire has a diameter of 4 mm and a total length of 30 cm. The magnetic field changes with time at a steady rate dB/dt = 0.032 Ts-1. The induced current in the loop is close to (Resistivity of the metal wire is 1.23 × 10⁻⁸ Ωm)
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Open question & full solution → - MCQmediumElectromagnetic Induction
At time t = 0 magnetic field of 1000 Gauss is passing perpendicularly through the area defined by the closed loop shown in the figure. If the magnetic field reduces linearly to 500 Gauss, in the next 5s, then induced EMF in the loop is : 16cm 2cm 4cm
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Open question & full solution → - MCQmediumAC Circuits
A series LR circuit is connected to a battery of emf V and switched on at t=0. The time at which inductor energy reaches 1/n of its maximum value is:
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Open question & full solution → - MCQmediumSimple Harmonic Motion
When a particle of mass m is attached to a vertical spring of spring constant k and released, its motion is y(t) = y₀ sin²(ωt), where y is measured from the lower end of the unstretched spring. Then ω is:
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Open question & full solution → - MCQmediumRotational Motion
A uniform cylinder of mass M and radius R is to be pulled over a step of height a (a < R) by applying a force F at its centre 'O' perpendicular to the plane through the axes of the cylinder on the edge of the step (see figure). The minimum value of F required is:
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Open question & full solution → - MCQmediumNuclear physics
Given: mass(⁷₃Li) = 7.0160 u, mass(⁴₂He) = 4.0026 u and mass(¹₁H) = 1.0079 u. When 20 g of ⁷₃Li is converted into ⁴₂He by proton capture, find the energy liberated in kWh. Use 1 u c² ≈ 1 GeV.
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Open question & full solution → - MCQmediumCapacitor
A parallel-plate capacitor has plate area A and separation d. It is filled with a dielectric whose dielectric constant varies as k(x) = K(1 + αx), where x is measured from one plate. If αd ≪ 1, the capacitance is best approximated by:
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