Within the S.I. (International System of Units), identify the base quantities from the following sets and items: length, mass, time, temperature, amount of substance (mole), luminous intensity, and electric current.

Difficulty: Easy

Correct Answer: all the above.

Explanation:


Introduction:
SI (Système International) defines seven base quantities forming the foundation for all derived units in science and engineering. Recognizing which physical quantities are base quantities is essential for dimensional analysis, unit conversion, and checking the consistency of formulas and results.


Given Data / Assumptions:

  • Base quantities in SI include: length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity.
  • The corresponding SI base units are metre (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), and candela (cd).


Concept / Approach:

If each option lists one or more base quantities, then the inclusive choice that acknowledges all correct items should be selected. The groupings in the options each contain valid base quantities.


Step-by-Step Solution:

Option A: length, mass → base quantities → correct.Option B: time, temperature → base quantities → correct.Option C: mole (amount of substance), light intensity (luminous intensity) → base quantities → correct.Option D: electric current → base quantity → correct.Therefore, the comprehensive answer is E: all the above.


Verification / Alternative check:

Dimensional symbols for base quantities are typically L, M, T, I, Θ, N, and J (for length, mass, time, electric current, temperature, amount of substance, luminous intensity respectively). Each listed quantity maps to a recognized base dimension.


Why Other Options Are Wrong:

  • A–D are individually correct but incomplete; only E captures all base quantities shown.


Common Pitfalls:

  • Confusing base quantities with derived ones such as force (newton) or pressure (pascal).
  • Assuming 'weight' is a base quantity; it is a force derived from mass and acceleration.


Final Answer:

all the above.

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