Calculating Work to Stop a Moving Electron

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To calculate the work required to stop a moving electron, the relevant formula is W = ΔKE, where ΔKE represents the change in kinetic energy. The initial kinetic energy (KE) of the electron is determined using the equation KE = 1/2 mv^2, with the mass of the electron being 9.11×10^-31 kg and its speed 1.86×10^6 m/s. Since the final kinetic energy is zero when the electron stops, the work done is equal to the negative of the initial kinetic energy. The discussion emphasizes that there is no potential energy involved in this scenario. Ultimately, the calculation simplifies to determining the initial kinetic energy to find the work needed to stop the electron.
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How much work is required to stop an electron (m = 9.11×10-31 kg) which is moving with a speed of 1.86×106 m/s?

Ef-Ei=W
Kenetic E - Potential E = Work
I don't think there is any potential energy in this case...

I'm a bit stuck. Any suggestions?
 
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Keep going. W = \Delta {KE}, so what's the kinetic energy of that electron?
 
is the change in kenetic energy 1/2mv^2?
 
The initial KE of the electron is 1/2mv^2; the final is zero. So, yes, the change in KE is (minus) 1/2mv^2.
 
Great thank you that was a whole lot easier than I made it out to be!
 

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