Speed of Light [ENDORSED]

[cbenitez3e]

Is it better to use c=3x10^8 or c=2.998x10^8 like it is stated in the textbook?

[Salman Azfar 1K]

I haven't seen any specific guidelines but more significant figures will usually lead to the more accurate answer, so I wouldn't really recommend using 3.0 unless you're in a rush or something.

[Madeline Musselman 3H]

I think that it would be better to use 2.998x10^8 as the speed of light in order to get a more precise and accurate answer. However, using 3.00x10^8 won't dramatically affect your answer.

[ConnorThomas2E]

Typically, I use the more precise number because I try to limit the possible rounding errors that could affect my answer. I also try doing this by keeping the whole numbers in my calculator and try as little to possible to round until I get my final answer. However, as other people are saying, there is not much difference between 3.00x10^8 and 2.998x10^8, so there won't be a large effect on your answer.

[Alyssa Pelak 1J]

Lavelle uses 3.00x10^8 when solving his problems, so I think it would be fine to use this one. Either will work though!

[Dang Lam]

I prefer to use 2.998x10^8 because it gives a more accurate and precise answer. It's like when we calculated the moles in the previous chapter, we carried all the decimal points until the final answer then we rounded it. But if you feel more comfortable using 3.00x10^8 then it should be fine too. :)

[Maria1E]

My TA told us to use whatever number is given to us on the equation sheet on the front page of the test, just to be safe. But either way should work!

[Yixin Angela Wang 2H]

If I need a precise answer, I use as many significant digits as I am given. However, if I am solving something for a ratio or something where rounding does not change the final outcome, I will use a more general number and save some time.

[Matthew Lee 3L]

I don't think that it really matters that much. Dr. Lavelle uses 3.00x10^8, so that should work. The 2.998x10^8 should be equally as good or better, since it is closer to the exact speed of light!