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Hi, just some quantum physics questions. I've given them all a good go, the first two just require checking, but the rest I'm rather stuck on. They're the last questions in about 20 other ones, and my head now hurts. :(
Any hints are very much appreciated!
I firstly got converted the 5eV to joules which gave m 8 x 10-19. I then divided that by the Planck's constant to get my final answer of 1.21 x 1015Hz
I got the wavelength of 2.49 x 10-7, by dividing the speed of an EM wave by the answer to A.
I'm afraid this is where I get stuck. The possible equations that I know are KE = 0.5mv2 and hf = φ + ½ mv2max but here I am unsure of the theory. :(
Pretty sure this is the particle model. Unsure of how to calculate the wavelength though, any ideas?
I'm pretty sure this is the wave model. Same as the previous question.
Thanks for reading!
Any hints are very much appreciated!
Homework Statement
17. Metal X has a work function of 5.0 eV and is used in a demonstration of the photoelectric effect.
a) What is the min. frequency needed to remove electrons from X?
I firstly got converted the 5eV to joules which gave m 8 x 10-19. I then divided that by the Planck's constant to get my final answer of 1.21 x 1015Hz
b) What is the wavelength of these waves?
I got the wavelength of 2.49 x 10-7, by dividing the speed of an EM wave by the answer to A.
c) If metal X was irradiated with EM waves of frequency 2.0 x 1015 Hz, what will be the maximum kinetic energy of the photoelectrons released?
I'm afraid this is where I get stuck. The possible equations that I know are KE = 0.5mv2 and hf = φ + ½ mv2max but here I am unsure of the theory. :(
18. In the following two situations, calculate the de Broglie wavelength and, hence, state whether the particle or the wave model should be used.
a) Neutrons (m=1.8x10-28kg) moving at 107ms-1 passing a gap of 8x10-10m
Pretty sure this is the particle model. Unsure of how to calculate the wavelength though, any ideas?
b) Electrons with a momentum of 4x10-19kgms-1 passing nuclei diameter 10-15m
I'm pretty sure this is the wave model. Same as the previous question.
Thanks for reading!