Recent content by JDiorio

THANK YOU! yeah i just did it with that number. So stupid. I use 13.2 hrs and it was 13.1. thanks a lot.

so I've done a little more research and I am not sure about my original hypothesis now.. I have found that the frequency at which the light is emitted is much more important then the intensity. If a "critical frequency" is not met, then no electrons will be emitted despite how intense the light...

Just wondering, how could you influence the number of photons emitted from a metal surface. I would assume that increasing the intensity of the light would cause an increase because the intensity is a measure of the amount of photons traveling in the light. But what about other factors such as...

I don't want to keep bumping this thread.. but i really need to know what I am suppose to do.. i have one more attempt at this problem on my homework site and i need all the points i can get.. I just need to know what is wrong with this answer

so is this answer correct?? because when i typed it in .. it said it wasn't..

yeah i copied this directly from my homework site.. hmm.. its telling me that it is the wrong answer.. not sure what to do.. but it definitely says 24 days..

Homework Statement A patient with thyroid problems has radioactive iodine 123 deposited in his thyroid gland. If the iodine has an initial activity of 2.5 MBq, what is its activity after 24 days? Homework Equations A(t)= Ao e^ -(ln(2)/half-life)*t The Attempt at a Solution not...

UGH!... I am using the E button on my calculator and didn't account for an extra.. i was doing 1E8 instead of 10E8.. thanks for the help.. really appreciate it..

my calculations were as follows: (ln(2)/half-life)t = .0985 and then i just calculate e^ -.0985 and now i got .906.. and then when i multiply by the .77 I get .697

well i looked it up and found that it was equal to 7.04E8.. sorry that i did not include this information.. it wasn't included in the original question but i looked it up in the textbook.. but with that information, am i going about solving the problem correctly?

Homework Statement At present, the concentration of uranium 235 in naturally occurring uranium deposits is approximately 0.77%. What will the concentration be one billion years from now? Homework Equations N(t) = No e^ -(ln(2)/half-life)t The Attempt at a Solution i attempted...

Thank you!..

ohh.. so i just use F= kq1q2/r^2 and since it is in the n=1 state, i would use Bohr's radius for r... correct?

Homework Statement In the Bohr model of a hydrogen atom, what is the magnitude of the electric force exerted between the proton and the electron when the electron is in the n = 1 state? Homework Equations E= - 13.6 eV/ n^2 The Attempt at a Solution I simply...

thanks a lot for everyone's help!