Step 2: Rearranging to Find Kinetic Energy We can rearrange the formula to find kinetic energy k:λ2=‌
h2
2mk
So, k=‌
h2
2mλ2
Step 3: Substitute the Values Here, Planck's constant, h=6.6×10−34Js Mass of electron, m=9×10−31kg Wavelength, λ=2nm=2×10−9m Now substitute these into the formula: k=‌
(6.6×10−34)2
2×9×10−31×(2×10−9)2
Step 4: Calculation Calculate the value: k=‌
(6.6×10−34)2
2×9×10−31×(2×10−9)2
This gives: k=0.608×10−19J Step 5: Convert Joules to Electron Volts 1 electron volt (eV)=1.6×10−19J. So, k=‌
0.608×10−19
1.6×10−19
eV=0.38eV The kinetic energy of the electron is about 0.38 eV .
