The e.coli bacterium is about 2.3 μm long. Suppose you want to study it using photons of that wavelength or electrons having that de Broglie wavelength.
What is the energy E photon of the photon?The e.coli bacterium is about 2.3 μm long. Suppose you want to study it using photons of that wavelength or electrons having that de Broglie wavelength.
What is the energy E photon of the photon?
I found the energy of the photon to be 8.6 x 10^-20
What is the energy Eelectron of the electron?
Im using the equations given but I am getting the wrong answer everything time, can someone help? Thank You
achieve #13
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Re: achieve #13
Hello!
I started with Ee- = 1/2 mv^2 (kinetic energy for the electron) and deBroglie's = h/p = h/mv
Rearranging debroglie's to be v = h / m and substituted that for the kinetic energy equation
So, the final equation I used was Ee- = 1/2 * me(h / [m*e^2])
I started with Ee- = 1/2 mv^2 (kinetic energy for the electron) and deBroglie's = h/p = h/mv
Rearranging debroglie's to be v = h / m and substituted that for the kinetic energy equation
So, the final equation I used was Ee- = 1/2 * me(h / [m*e^2])
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Re: achieve #13
To find the energy of the electron, use the equation for kinetic energy (1/2mv^2). Using De Broglie's, solve for velocity so that v = h/(m*wavelength). Using this, I found velocity after plugging in Planck's constant, mass of an electron, and the given wavelength (making sure to convert to the right units). Then take the velocity and plug it into the equation for kinetic energy to find the energy of the electron.
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Re: achieve #13
Hi,
So the thought process for this question is as followed:
It asks you to determine the energy of the electrons, which can be calculated through the equation Ek=1/2mv^2. However you do not know the velocity of the electrons, so you would need another set of equations to determine this. From the information given and constants, you know the wavelength, and the mass of electrons. With these information you can use the De Broglie equation which is λ=h/p, where p=mv, so λ=h/mv. Since the only unknown variable is the velocity, you would need to rearrange the equation to separate the variable 'v'. Thus you would get v=h/λm. Substituting this into the unknown 'v' of the kinetic energy equation you would get, Ek=(1/2)m(h/λm)^2. And now since you know all the variables in the equation you can plug in the values and calculate for the energy of electrons.
So the thought process for this question is as followed:
It asks you to determine the energy of the electrons, which can be calculated through the equation Ek=1/2mv^2. However you do not know the velocity of the electrons, so you would need another set of equations to determine this. From the information given and constants, you know the wavelength, and the mass of electrons. With these information you can use the De Broglie equation which is λ=h/p, where p=mv, so λ=h/mv. Since the only unknown variable is the velocity, you would need to rearrange the equation to separate the variable 'v'. Thus you would get v=h/λm. Substituting this into the unknown 'v' of the kinetic energy equation you would get, Ek=(1/2)m(h/λm)^2. And now since you know all the variables in the equation you can plug in the values and calculate for the energy of electrons.
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Re: achieve #13
I started by just combining and simplifying the kinetic energy equation (E = 1/2 * mv^2) and deBroglie's equation (lambda = h/mv).
Since we are trying to solve for E but also don't know velocity, I made deBroglie's equation equal to v =, instead of lambda=. Then, I plugged in the v = modified deBroglie's into the kinetic energy equation. Since now, the only values are m, lambda and h, which we all know, it is just a matter of plugging in.
Since we are trying to solve for E but also don't know velocity, I made deBroglie's equation equal to v =, instead of lambda=. Then, I plugged in the v = modified deBroglie's into the kinetic energy equation. Since now, the only values are m, lambda and h, which we all know, it is just a matter of plugging in.
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Re: achieve #13
I first made sure to convert the length to meters. To find the energy of the photon, I used the equation Ephoton = hc/lambda. Then, to find the energy of the electron, I used the de Broglie equation where lambda = h/mv to find the velocity and used the energy of an electron = 1/2mv^2. I plugged in the known values into the first equation to find the velocity and plugged it into the second equation to find the energy of the electron.
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