Physical Constants

Reference: National Institute of Standards and Technology (NIST)

http://physics.nist.gov/cuu/index.html

FAQ: Do I need all these decimal places?

When doing a calculation, the constants should be more precise than the other values.

For example, if the given values in a homework question all have three significant figures, then c = 2.998×108 m/s is sufficient because it will not limit the precision of your answer.