How Do You Convert and Round Measurements to SI Units with Significant Figures?

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SUMMARY

This discussion clarifies the conversion and rounding of measurements to SI units with significant figures, specifically focusing on Joules (J) and kilojoules (kJ). Both J and kJ are acceptable SI units, with kJ being the preferred form for larger values. The correct representation of significant figures is crucial; for example, 589883.4263 J should be expressed as 590 kJ when rounded to three significant figures. Additionally, the importance of case sensitivity in unit prefixes is emphasized, as "kJ" must be written with a lowercase 'k'.

PREREQUISITES
  • Understanding of SI units, specifically Joules and kilojoules
  • Knowledge of significant figures and rounding rules
  • Familiarity with unit conversion principles
  • Awareness of case sensitivity in scientific notation
NEXT STEPS
  • Research the rules for rounding numbers in scientific contexts
  • Learn about the significance of unit prefixes in SI units
  • Explore conversion techniques between different SI units
  • Study examples of significant figures in scientific measurements
USEFUL FOR

Students in physics or chemistry, educators teaching measurement concepts, and anyone involved in scientific calculations requiring precision in unit conversion and significant figures.

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Homework Statement



If I am asked to give my answer in acceptable SI units and to 3 significant figures, how would I express my answer?

Homework Equations



Answer: 589883.4263 J

The Attempt at a Solution



My instinct would be to put this in KJ, but I don't know if that's an "acceptable SI unit". I can't find anything about it online. Does it have to stay in J?

If KJ I would write it as 590 KJ, right?

and if I had something like 1674.324432 J, would I express it as 1670 J or 1.67 KJ? I'm really confused.

Thanks
 
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Both J and kJ are perfectly acceptable SI units. The base unit is the Joule, of course, in case that's what they are looking for.
 
Note that its kJ, not KJ. Case is important in many prefixes.
 
Orodruin said:
Note that its kJ, not KJ. Case is important in many prefixes.

Oh wow...I actually think that was the problem. I used J this time and got it right but thanks for that heads up
 

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