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Units and Measurements

Need for measurement: Units of measurement; systems of units; SI units, fundamental and derived units. Length, mass and time measurements; accuracy and precision of measuring instruments; errors in measurement; significant figures. Dimensions of physical quantities, dimensional analysis and its applications.

Dimensions of Physical Quantities

The nature of physical quantities is described by its dimensions. All the physical quantities represented by derived units can be expressed in terms of...

Significant Figures

Significant Figures: As discussed above, every measurement involves errors. Thus, the result of measurement should be reported in a way that indicates the precision...

Combination of Errors

The combination of Errors: Error of A Sum or A Difference Error of A Product or A Quotient Error in case of a measured...

Absolute, Relative, and Percentage Error

Arithmetic Mean or Average Value: Let the value obtained in n measurements are a1, a2, a3...., an. Then, the Arithmetic Mean or Average Value of...

Accuracy, Precision and Errors

Error: The result of every measurement by any measuring instrument contains some uncertainty. This uncertainty is called error. Every calculated quantity which is based on...

Measurement of Mass and Time

Measurement of Mass: Mass is a basic property of matter. It does not depend on the temperature, pressure or location of the object in space....

Measurement of Length

Measurement of Length: You are already familiar with some direct methods for the measurement of length. For example, a meter scale is used for lengths from...

Measurement, SI units and System of Units

The comparison of any physical quantity with its standard unit is called measurement. Physics is a quantitative science, based on measurement of physical quantities. Certain...