sig figs/appropriate decimal values

[Deceitful Wings]

Do the same rules as chem apply or are they more relaxed about it?
What is the most appropriate number of sig figs for the values we get?

[Aurelian]

The same rules as chem apply, but they don't really care. Just don't quote an unreasonable number of figures and you'll be fine. Often for physics, if the question would typically demand only one or two significant figures, I'd actually quote three anyway. Just use your discretion, but yeah - they don't really take marks off like chem =)