Achieve Assignment #2, Question #15

[trishaferrer]

Hi! Can someone help me with this? Thanks!

[Alexander Moroz 1B]

First convert 0.0151 nm to m with the conversion 1m=e-9nm

Then use the de Broglie equation to get velocity of the electron: wavelength=h/mv using mass of electron and planks constant

Use the velocity of electron to get kinetic energy through the equation KE=1/2mv^2

finally, convert energy in joules to eV through the conversion 1 eV = 1.602e-19 J

[carrie_karchmer_3D]

To solve this problem, I used De Broglie's ( wavelength = h/mv). Since we're given the wavelength, but not the velocity, I converted the equation to v=h/m 8 wavelength. Then I solved for the velocity. Once I got the velocity, I plugged it into KE = 1/2mv^2 to find the kinetic energy. Then I converted from j to eV (1 ev = 1.602 x 10^-19)

[Jayden Tan 2L]

Hi there!!

To solve, I first used De Broglie's wavelength equation to find the velocity of the electron because we need to use the velocity in order to find the kinetic energy. From there, I plugged in the mass of an electron and the velocity that we found into KE = 0.5*m*v^2 to find kinetic energy!! Since the question is asking for the energy to be expressed in eV, we convert using the conversion in the Constants and Formula Sheet. Hope this helps!

[Gabriel Wolf 3I]

Because it is asking for electron kinetic energy, and not photon energy, you have to use the kinetic energy equation for electrons. That's essentially just plug and chug, so all you have to do on your own is convert the nanometers to meters, and you should be able to just plug that in and find the answer. The output, however, will be in joules, so just use the conversion factor that is also in the given sheet of constants and equations.

[Maxwell Yao]

First you have to convert the wavelength into meters and then you use the DeBroglie equation to solve for velocity.

Then you can plug the velocity value you found into the equation for Kinetic Energy which is KE = 1/2mv^2

Then finally you just convert to electron volts (eV).

Hope this helps.

[Madelyn_Rios_2c]

1) convert .0151 nm to m
2) Find the velocity by rearranging Broglie's equation: v= h/(m* lambda)
3) use the equation E_k= (1/2)(m*v²) to find the kinetic energy
4) convert the energy from joules to eV by 1eV = 1.602 x 10^-19 J

[Aaron Martinez]

Using de Broglie's equation, wavelength = h / mv, we can find the velocity of the electron because the wavelength is given.
Rearranging the equation gives, v = h / (m*wavelength)
Convert nanometers to meters and use the given weight of the electron from the constants and equations sheet, plug in the values
Using the found velocity, use the .5mv^2 equation to find the energy in J
Finally, convert to eV