How do significant digits work in physics calculations?

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Jayak
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A guitar string vibrates 750 times in 3.00s. Calculate period and Frequency.

I am in grade 11 and it is my first week in physics 11 so I'm new at this! My question is on how the significant digits work. I don't know where I should leave my answer..Here is my attempt:

Period: 3.00/ 750 = 0.0040s.. is that right with the about of sig fig?

Frequency 750/3.00 = 250hz

Help me! Thanks
 
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Jayak said:
A guitar string vibrates 750 times in 3.00s. Calculate period and Frequency.

I am in grade 11 and it is my first week in physics 11 so I'm new at this! My question is on how the significant digits work. I don't know where I should leave my answer..Here is my attempt:

Period: 3.00/ 750 = 0.0040s.. is that right with the about of sig fig?

Frequency 750/3.00 = 250hz

Help me! Thanks

As a rule of thumb, take your answer out to the number of significant digits given in the problem. For example, if you are given that some quantity of the problem equals 0.751, you were given three significant figures. Thus, if you put something in your calculator and get an answer out to 10 decimal places, you should only take three significant figures. Also, it is generally a good idea to give an answer out to the least number of significant figures given in the question. In your case above, the quantity 3.00 has three significant figures, while 750 has only two. Therefore, your answer should most reasonably have two significant figures, which you did! Hope this helps!