Question

A moving electron has a de broglie wavelength 7 x 10-7m.Calculate its kinetic energy

Answer 1

A moving electron has a de Broglie wave length of 7 x 10-7 m. calculate its kinetic energy. (Planck's. constant = 6.626 x 10-34 Js, mass of anelectron = 9.1 x 10-31 kg)

Answer 2

​Dear Student,

We know that, λ=hmvor, v=hmλor, v=6.626×10−34 Js9.1×10−31 kg×7×10−7 m=1040.18 ms−1Now, K.E.=12mv2or, K.E.=12×(9.1×10−31 kg)(1040.18 ms−1)2or, K.E.=5×10−25 J
​Thank you