URGENT!!! iTute 2010 question

[jackchan1993]

Question 11 of the Interactions of light and matter section

the energy states are   n=1:-10.4eV   n=2:-5.5eV    n=3:-3.7eV     n=4:-1.6eV     n=5:0

It asks: Describe the result of a collision between a PHOTON of energy 11.3 eV and mercury atom in the ground state.

I said nothing happens because if it is a PHOTON its energy must match exactly with the energies of the different discrete energy states. But the answers stated:

"Ionisation of the mercury atom can occur because the
photon energy (11.3 eV) is greater than the ionisation energy
(10.4 eV). The electron emitted will have 11.3 −10.4 = 0.9 eV of
kinetic energy."

I thought this was only the case with a beam of "electrons" fired at the atom, that the energies didn't have to match with the discrete energy states.

[Whatlol]

if you have a photon with an energy greater than ionisation energy, it will cause the ejection of an electron which will posses the remainder of the energy. e.g this is observed in the photoelectric effect.

[jackchan1993]

Ohh! I get it now... thanks mannnnn

[Whatlol]

Ohh! I get it now... thanks mannnnn

no probs, good luck.

[waack]

the incident photon or electron (doesnt matter which) has enough energy to ionise the. Obviously if the photon strikes an electron with greater energy then the ionising energy it will eject it its not relevant whether it is a electron or photon. But if it is below the ionising energy you are right and the photon can only be aborbed if it matchs perfectly wheras an electron can be aborbed and it will just go to the highest possible

[jackchan1993]

guys how do i give +karma LOL im so noob

wanna give u guys karmas cos so nice

[Whatlol]

guys how do i give +karma LOL im so noob

wanna give u guys karmas cos so nice

gotta have over 50 posts, dont worry about it

[jackchan1993]

awwww thanks anyways

[t3nsai]

what would happen if a proton collides with the atom?

[waack]

not 100% sure but seeing as it is 'matter' like electron and not an 'energy packet' like a photon i would asssume same as electron but dont quote me

[3Xamz]

what would happen if a proton collides with the atom?

That's not in the physics course to the best of my knowledge ><