Question

A particle has a velocity that is 70 % of the speed of light and weighs 206.8 times the mass of an electron. Find the wavelength of this particle?

Answer 1

Speed of light = 3x10^8 m/s
Mass of electron = 9.11x10^-31 kg

70% of 3x10^8 = 2.1x10^8 m/s
206.8*9.11x10^-31 = 1.88x10^-28 kg

Equation for wavelength is: wavelength= plancks constant / (mass*velocity)

Plancks constant = 6.62x10^-34 m^2 kg/s

Plug all of these in and you get: 6.62x10^-34 / (1.88x10^-28/2.1x10^8) = 739.47

Your answer is 739.47 m