How Fast Must an Electron Travel to Excite a Hydrogen Atom?

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The discussion centers on calculating the speed required for an electron to excite a hydrogen atom, with the first excitation energy specified as 10.2 eV. The kinetic energy of the electron, expressed as 1/2 mv^2, must equal the excitation energy to achieve this. The electron charge/mass ratio and constants like Planck's constant and the speed of light are provided for reference. The calculated speed of the slowest electron necessary for this excitation is 1.9 x 10^6 m/s. The conversation emphasizes the relationship between kinetic energy and excitation energy in atomic physics.
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i hav problem solving this.. help please?

The 1st excitation energy of hydrogen atom is 10.2eV
calc the speed of the slowest electron that can excite a hydrogen atom..

(electron charge/mass ratio e/m = 1.7 x 10^11 C kg-1)

C(speed of light ) is 3 x 10^8 ms-1
h(planks constant) is 6.6 x 10 ^ -34 Js

thats all the given information

the answer is 1.9 x 106ms-1
 
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The kinetic energy of the electron gets transferred to the excitation energy of the hydrogen atom.

Can you express that statement in an equation?

p.s. Welcome to PF.
 
er..

hf = work function energy?

1st excitation energy is work function energy?
speed of the slowest electron is the hf oso = 1/2 mv^2?
 
Redbelly98 said:
The kinetic energy of the electron gets transferred to the excitation energy of the hydrogen atom.

ke0nGz said:
speed of the slowest electron is the hf oso = 1/2 mv^2?

You're half-way correct, since 1/2 m v^2 is the kinetic energy of the electron.

What is the excitation energy of the atom?
 

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