What does quantities and dimensions mean?

AI Thread Summary
Quantities refer to measurable attributes like velocity or force, while dimensions represent the nature of these quantities, such as length. Different units can express the same dimension, meaning two quantities can share the same dimension but differ in units. For example, height can be measured in inches or centimeters, illustrating that the dimension remains constant despite unit variation. The discussion clarifies the distinction between quantities and dimensions, emphasizing their relationship in measurement. Understanding this concept is essential for accurate communication in scientific contexts.
elton_fan
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i would like to ask a question about what does quantities and dimension mean in this sentence
is it possible for two quantities to have the same dimensions but different units?

thanks a lot in advance
 
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elton_fan said:
i would like to ask a question about what does quantities and dimension mean in this sentence
is it possible for two quantities to have the same dimensions but different units?

thanks a lot in advance


A physical quantity is something that can be measured, for example, velocity, force, etc. The quantity is expressed in units, which are not to be confused with the term 'dimension'. The term 'dimension' needn't be used, actually.
 
"Length" is an example of a dimension. The "meter" is an example of a unit, one that can be used to express lengths.

- Warren
 
so for example what would be the answer of this question?
i think it's yes
it's true
 
Last edited:
elton_fan said:
so for example what would be the answer of this question?

I'll answer your question with a question. How tall are you in inches? How tall are you in centimeters? Your height dimension is the same, no matter what units you use to express that height.

Think of a particular shipping box. It has linear dimensions of length, width and height. And those dimensions can be measured using various unit systems.
 
thanks a lot i understand now
 
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