Recent content by mss90

a as in protons+neutrons, z as in protons and n as in neutrons, x = the element. Sorry for confusion caused but wasnt sure how to write it.

Homework Statement If azXn is an unstable parent nucleus, write down expressions showing the products of the β + and β - decay of this nucleus. Homework Equations I have no idea how do do this, I recon its quite simple but.. Could anyone give me a pointer? The Attempt at a Solution none

Homework Statement A wavelenght of 410.2*10^-9m is emitted by the hydrogen atom in a high voltage discharge tube. what are the initial and final values of the quantum number n for the energy lvl transition that produces this wavelength? Homework Equations 1/(lambda) = R * (1/2^2 - 1/n^2)...

Homework Statement particle pass through a slit of width 0.200mm. the wavelength is 633nm. after it pass through the slit they spread out over a range of angles . use uncertainty principle to determine the min. range of angles. Homework Equations (delta)p*(delta)y = h/4(pi) The Attempt at a...

Homework Statement how many photons (lambda=620*10^-9) must be absorbed to melt 2kg block of ice at 0deg into water at 0deg? and on average, how many H2O molecules does one photon convert from the ice phase to water phase? Homework Equations E=hc/lambda The Attempt at a Solution I have no idea...

ah ye, there we go. thanks :)

Ek=(hc/lambda)-W ((6.63*10^-34)*(3*10^8))/(2.15*10^-7) - (5.888*10^-9) (9.25*10^-19) - ( (5.888*10^-9) = -5.887*10^-9 J / (1.6*10^-19) = -3.68*10^10eV

Homework Statement A magnesium surface has a work.func of 3.68eV. El.mag. waves with wavelenght of 215nm strike the surface and eject electrons. Find the max Ek of the ejected electrons in eV. Homework Equations E=Ek-W <=> Ek=(hc/lambda) - W The Attempt at a Solution I convert eV to J and nm...

Alright in that case we know the half life and can find the decay constant. Using A = -(lambda)*N we can find N as well (not sure If I need to divide the activity on 9.2g to get it per grams?) However It still leaves No and t unsolved. An alternative method is to; N=No * e ^ -(lambda)*t...

Homework Statement 9.2g of carbon got an activity of 1.6Bq, how old is it? Homework Equations A = -(lambda)*N N=No * e ^ -(lambda)*t (lambda) = ln2/t1/2 The Attempt at a Solution The question doesn't specify which isotope of carbon it is so halflife remains unknown. I can't see how to solve...

m= 9.11E-31kg ħ=h/2pi a=(pi2 ħ2/E2m)*12 a=1.66E-34/2.3E-30 a= 7.22E-5eV I tried this

Im thinking En = h2kn2/(2m) or En = n2π2ħ2/(2mL2)?

Homework Statement If a particle (infinite 1-D well) in ground state n =1 with an energy 1.26 eV above E=0. Whats the energy needed to get it to 3rd excited state n =4? Homework EquationsThe Attempt at a Solution any hints?

aaah that's embarrassing, its E on top :p E=k(Z-1)2 ó k=E/(Z-1)2 8.03 / (29-1)2=0.0102 25 / (50-1)2 =0.0104 Average = 0.0102+0.0104/2=0.0103 E=k(Z-1)2 hence E=0.0103 *(82-1)2 = 64.32KeV

Ye but it still doesn't line up, right?