The question asks: "You use an electron microscope in which the matter wave associated with the electron beam has a wavelength of 0.0227 nm. What is the kinetic energy of an electron in the beam, expressed in electron volts?"
I'm not sure which equation to use for this equation since there are multiple, how would I approach this problem?
Achieve Question 15
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Re: Achieve Question 15
Hi!
For this problem, what we need to find is the kinetic energy, which is KE = 1/2mv^2. Notice that we are missing v, which is the velocity. To find the velocity, we can refer back to DeBroglie's equation, since we know Planck's constant, the mass of an electron, and also the wavelength. Essentially, we work backwards to determine the equations needed.
lambda = h/mv -> v =h/mlambda -> find v
KE = 1/2(mass of electron)(v^2)
Convert KE to eV (1.602*10^-19 J = 1eV)
I hope this helps
For this problem, what we need to find is the kinetic energy, which is KE = 1/2mv^2. Notice that we are missing v, which is the velocity. To find the velocity, we can refer back to DeBroglie's equation, since we know Planck's constant, the mass of an electron, and also the wavelength. Essentially, we work backwards to determine the equations needed.
lambda = h/mv -> v =h/mlambda -> find v
KE = 1/2(mass of electron)(v^2)
Convert KE to eV (1.602*10^-19 J = 1eV)
I hope this helps
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