# Recent content by physics(L)10

1. ### T-butyl vs. isopropyl subsitutions

Homework Statement T-butyl chloride can undergo substitution reaction to create C4H9OH, but isopropyl chloride cannot. Why is this? Homework Equations The Attempt at a Solution I'm guessing it has to do with the extra carbon. Maybe since it is a secondary halide, the substitution...
2. ### Substance decrease by factor of 100? (radioactivity)

Yes, I just forgot to put it in. Thanks for your help :)
3. ### Principal Quantum number by size?

Alrighty, thank you very much :)
4. ### Substance decrease by factor of 100? (radioactivity)

Ok I think I got it: N(o)/100 = N(o)e-kt 1/100 = e-kt ln(1/100) = e-kt ln(1/100) = -[(ln2)/8](t) 53.1 days = t
5. ### Principal Quantum number by size?

So I'm right? The answer is just 97? I thought the principal quantum numbers (n) only go up to like 5 or 6 or something like that though.
6. ### Substance decrease by factor of 100? (radioactivity)

Homework Statement Radioactive iodine (131-I) has a half life of 8 days. How long does it take for iodine to be reduced by factor of 100? Homework Equations N(t)=N(o)e-kt k=ln100/t1/2 The Attempt at a Solution N(t)=N(o)e-kt N(t)/N(o)=e-ln(100/8)t Now I'm stuck. I would...
7. ### Principal Quantum number by size?

Homework Statement What is the value of the principal quantum number for a hydrogen atom to have a size of one micron? Homework Equations r=(5.3x10-11)(n2) r=1x10-6/2=5x10-7 The Attempt at a Solution 5x10-7=(5.3x10-11)(n2) 97.1 = n How is this possible? lol Maybe it's more complicated...
8. ### Charge on each mass?

Alrighty, thanks alot :)
9. ### Charge on each mass?

Well I don't know what to do then lol.
10. ### What is electric field problem?

So then the final answer is 3.6Coulombs?
11. ### What is electric field problem?

I posted it above ^ you didn't say if its correct or not lol.
12. ### What is electric field problem?

Don't you divide 2mm by 100 twice to get to m? Yes, A is 0.36m. They give the dimensions of the plates as .6mx.6m Yup, that's what they give in the question. It says charge density is 10 Coulombs/m2
13. ### Charge on each mass?

Nope, I double-checked the problem and I wrote it exactly the same. Is it possible we can used substitution? Ex, solve for q and then plug it back in to solve for r.
14. ### What is electric field problem?

Ooooooh I see, thanks, you made that really clear. So, E = (1.13 x 1011)(10) = 1.13x1012 Coulombs/m2 b) V = EL = (1.13x1012)(.0002m) = 2.26x108Volts c) I'm gonna attempt this one and say that since you said E = (1.13 x 1011)(Q/A), then: 1.13x1012=(1.13x1011)(Q/.36) 27.8 coulombs =...
15. ### What is electric field problem?

a) Well it gives 10 Coulombs/m2 which equals Q/A, so how do I relate this to E=1.13x1011 Q/A? b) V=(answer in A)(.00002m) c) I still don't quite understand