Chapter 2 Units and Measurements - Class 11 Physics
Chapter 2 Units and Measurements
NCERT Class 11 Physics for blind and visually impaired students made Screen Readable by Professor T K Bansal.
This Chapter is planned, organized and described by Dr. T K Bansal for blind and visually impaired students. All efforts have been made to make the chapter fully accessible by providing headings, describing figures and tables. The Chapter has been so designed that the students should enjoy studying this chapter and should move forward without any hurdles. The chapter has been thoroughly checked for any mistakes, still if you find any mistakes or have any suggestions to make it better, please write to us at ‘ blind2Visionary@gmail, or leave your comments at ‘www.blind2visionary.org’.com ‘. Your efforts will be highly appreciated.
Table of symbols used in this chapter:
| Symbol | Known As | Used For | Description |
|---|---|---|---|
| × | Times | Multiplication | Normal cross sign |
| − | Minus | Subtraction | A normal dash sign |
| θ | Theta | Plane angle | Looks like capital letter Q |
| Ω | Omega | Solid angle | Looks like small letter w |
| π | Pi | Angle subtended by a straight angle | A small horizontal line with 2 vertical lines below it |
| Α | Alpha | Angle | Greek letter alpha |
| Δ | Capital delta | Small Difference | Like a small triangle |
| Σ | Sigma | sigma | Summation |
| ′ | Prime | Minute of arc | Normal ‘ sign |
| ″ | Double prime | To make variables different | Like a “ sign |
| ∈ | Element of | Element of a set | Epsilon, a Greek letter |
| ~ | Tilde | About, of the order of | A wave like line |
| ≅ | Approximately equal to | Approximately equal to | A tilde over = sign |
| √ | Square root | Square root | |
| ° | Degrees | Degrees | A small circle in superscript |
| ∠ | Angle | Angle | 2 small lines meeting on the left |
| ÷ | Divided by | Division | Dots above and below a dash sign |
| ± | Plus or minus | Plus or minus | A plus sign above a minus sign |
| ≤ | Less than or equal to | Less than or equal to | Less than sign with a parallel line to the lower arm of less than sign |
List of headings :
2.1 Introduction
2.2 The international system of units
2.3 Measurement of length
2.4 Measurement of mass
2.5 Measurement of time
2.6 Accuracy, precision of instruments and errors in measurement
2.7 Significant figures
2.8 Dimensions of physical quantities
2.9 Dimensional formulae and dimensional equations
2.10 Dimensional analysis and its applications
2.11 Summary
2.12 Exercises
2.13 Additional exercises