What is the difference between a dimension and a unit? Give three examples of each.
The difference between a dimension and a unit.
Explanation of Solution
Dimension:
Dimension is defined as the measure of degree of freedom in mathematics. It is defined as the measure of physical quantity without including any numerical value. It tells us that all the independent quantities used to define the coordinates of the position or point. It falls under intrinsic property. Dimensions of complex quantity can be calculated by combining the seven-primary dimensions.
Unit:
Unit is the measurement of dimension by assigning a numerical value. It is defined as the physical quantity which gives standard value. They include numerical values to define dimensions. Unit tells a specific way to report a quantity. Units can be kept constant while doing algebraic calculations. Mathematical operations can only be performed if the dimensions of all the quantities are similar.
Sr. No. | Dimension | Unit |
1 | It is defined as the measure of physical quantity. | Unit is the measurement of dimension by assigning a numerical value. |
2 | It does not include numerical values. | They include numerical value to define dimensions. |
3 | Dimensions tells the nature of the quantity. | Unit tells a specific way to report a quantity. |
4 | Dimensions are an arbitrary chosen property (physical). | It helps in expressing dimension in numbers. |
5 | Examples- length, mass, time. | Examples- meter, kilogram, hour/second. |
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