Confusion regarding significant figures in answers

AI Thread Summary
The discussion centers on the confusion surrounding significant figures when converting units of speed, specifically from 0.4 m/s to km/h. The original poster questions whether 0.4 has one significant figure, which would affect the precision of the final answer. A participant clarifies that when multiplying or dividing values, the result should reflect the least number of significant figures present in the original terms. The original poster later acknowledges their misunderstanding and indicates that they have resolved their confusion. The conversation highlights the importance of understanding significant figures in calculations.
fleetingmoment
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Homework Statement


I'm working through some exercises in which I'm supposed to convert various units of speed from SI units to other units
Example: 0.4m/s into km/h

Homework Equations


upload_2017-1-27_0-53-30.png


The Attempt at a Solution


Having checked, I know my answer to be (to 3 significant figures) correct. My confusion arises regarding significant figures. Wouldn't 0.4 be 1 significant figure, which, if I remember and understand correctly, influences how the answer must be expressed, which in turn would leave me with a answer value of 1.
 
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Doesn't the exercise state explicitly how many significant figures are needed for the result?
 
fleetingmoment said:

Homework Statement


I'm working through some exercises in which I'm supposed to convert various units of speed from SI units to other units
Example: 0.4m/s into km/h

Homework Equations


View attachment 112152

The Attempt at a Solution


Having checked, I know my answer to be (to 3 significant figures) correct. My confusion arises regarding significant figures. Wouldn't 0.4 be 1 significant figure, which, if I remember and understand correctly, influences how the answer must be expressed, which in turn would leave me with a answer value of 1.

It's okay. I worked out where I was going wrong.
 
fleetingmoment said:
It's okay. I worked out where I was going wrong.
did you get the answer? when you are multiplying 2(or more) terms, the answer should contain as much as significant figures which is equivalent to that of the least number of significant figures containing term in the question.
 
harini07 said:
did you get the answer? when you are multiplying 2(or more) terms, the answer should contain as much as significant figures which is equivalent to that of the least number of significant figures containing term in the question.
oops sorry, just now i have seen that it's marked solved.ignore my useless rambling then :p
 

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