Calculate the de Broglie wavelength of a proton that has a k

Calculate the de Broglie wavelength of a proton that has a kinetic energy of 10 eV______________.

Solution

E = 1/2 mv² = (mv)² / 2 m = p² / 2 m

p = sqrt (2 m E)

de Broglie wavelength  = h / p

K.E given = 10 eV = 10 * 1.60 * 10^-19 J

lambda = (6.63 * 10^-34) / [ sqrt (2 * 1.67 * 10^{-27 *} 10 * 1.60 * 10^-19 ) ]

= 9.07 x 10^-12 m