jee_main_2025_28_jan_morning - System of Particles and Rotational Motion Topics

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QUESTION #19 Centre of Mass of Continuous Mass Distribution
The centre of mass of a thin rectangular plate (fig - x) with sides of length a and b, whose mass per unit area (sigma) varies as sigma = fracsigma_0xab (where sigma_0 is a constant), would be {{IMG1}}
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QUESTION #22 Moment of Inertia
The moment of inertia of a solid disc rotating along its diameter is 2.5 times higher than the moment of inertia of a ring rotating in similar way. The moment of inertia of a solid sphere which has same radius as the disc and rotating in similar way, is n times higher than the moment of inertia of the given ring. Here, mathrmn = _____. Consider all the bodies have equal masses.
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QUESTION #24 Moment of Inertia
Two iron solid discs of negligible thickness have radii mathbfR_1 and mathbfR_2 and moment of inertia mathrmI_1 and mathrmI_2 , respectively. For mathrmR_2 = 2mathrmR_1 , the ratio of mathrmI_1 and mathrmI_2 would be 1 / mathrmx , where mathrmx =
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JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%) | JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%)
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