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rubyred2012
Estimate the wavelength (in nm) of such a proton moving at 2.81x10^8 m/s (mass of a proton = 1.673x10^-27 kg).
\[E = \frac{1}{2}m v^2\] where m is the mass and v is the velocity \[E = \frac{hv}{\lambda}\] \[where \lambda \] is the wavelength. You can equate the two expressions for E, cancel the v and express the wavelength interms of h, m and v