jee_main_2026_28_january_evening - Units and Measurements Topics

Master these core formulas and structures to solve almost any past paper question.

Sample Questions in this Chapter

QUESTION #32 Least Count
In an experiment, a set of reading are obtained -1.24~mm , 1.25~mm , 1.23~mm , 1.21~mm . The expected least count of the instrument used in recording these readings is ____ mm.
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QUESTION #44 Errors in Measurement
The time period of a simple harmonic oscillator is T = 2π √((k)/(m)) . The measured value of mass (m) of the object is 10 g with an accuracy of 10 mg, and time for 50 oscillations of the spring is found to be 60 s using a watch of 2 s resolution. Percentage error in determination of spring constant(k) is ____%.
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QUESTION #45 Dimensional Analysis
Match List-I with List-II.
List-IList-II
A. Coefficient of viscosityI. [ML⁻¹T⁻²]
B. Surface tensionII. [ML²T⁻²]
C. PressureIII. [ML⁰T⁻²]
D. Surface energyIV. [ML⁻¹T⁻¹]
Choose the correct answer from the options given below :
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Rankbit System
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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