Skip to main content
Super TutorResources
Chapter 1 of 14
QuestionsNotesFlashcardsSummaryFormulasQuizConceptsSyllabusPlan
Revision Notes

Units and Measurements

CBSE · Class 11 · Physics

Quick revision notes for Units and Measurements — CBSE Class 11 Physics. Key concepts, formulas, and definitions for last-minute revision.

147 questions72 flashcards5 concepts

Interactive on Super Tutor

Studying Units and Measurements? Get the full interactive chapter.

Quizzes, flashcards, AI doubt-solver and a step-by-step study plan — built for revision notes and more.

Try Super Tutor — Free

1,000+ Class 11 students started this chapter today

Key Topics to Revise

1

1. Physical Quantities, Units, and Systems of Units

  • A physical quantity is expressed as a numerical value and a unit.
  • Measurement involves comparison with a basic, arbitrarily chosen, internationally accepted reference standard called a unit.
  • Fundamental or base quantities are independent quantities used to define other quantities.
2

2. SI Base Units and Retained Units

  • The seven SI base quantities are length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity.
  • The SI base units are metre, kilogram, second, ampere, kelvin, mole, and candela.
  • The metre is defined using the fixed numerical value of the speed of light in vacuum c.
3

3. Significant Figures and Scientific Notation

  • Significant figures show the precision of a measurement.
  • All non-zero digits are significant.
  • Zeros between two non-zero digits are significant.
4

4. Rules for Rounding Off and Error Handling

  • If the digit to be dropped is less than 5, the previous digit stays the same.
  • If the digit to be dropped is more than 5, the previous digit increases by 1.
  • If the dropped digit is exactly 5, the previous digit is kept unchanged if it is even and increased by 1 if it is odd.

Get complete notes with diagrams and examples

Full Notes

Key Concepts

Measurement of any physical quantity involvesThe fundamental or base quantitiesQuantities obtained from base quantitiesThe SI system is the internationallyRadian and steradian are dimensionless SI

Frequently Asked Questions

What are the important topics in Units and Measurements for CBSE Class 11 Physics?
Units and Measurements covers several key topics that are frequently asked in CBSE Class 11 board exams. Focus on the core concepts listed on this page and practise related questions to build confidence.
How to score full marks in Units and Measurements — CBSE Class 11 Physics?
Understand the core concepts first, then work through the 147 practice questions available for this chapter. Revise formulas and definitions regularly, and use flashcards for quick recall before the exam.

Sources & Official References

Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.

More resources for Units and Measurements

All 14 chapters — CBSE Class 11 Physics Revision Notes

For serious students

Get the full Units and Measurements chapter — for free.

Quizzes, flashcards, AI doubt-solver and a step-by-step study plan for CBSE Class 11 Physics.

Try Super Tutor Free
Try the full chapter — Free