1. The problem statement, all variables and given/known data A bullet of mass 39 g travels at 1060 m/s. Although the bullet is clearly too large to be treated as a matter wave, determine what Eq. 38-13 predicts for the de Broglie wavelength of the bullet at that speed? 2. Relevant equations de Broglie equation: wavelength = h / p where h is Planck constant and p is the particle's momentum magnitude. 3. The attempt at a solution p=sqrt(2*m*K) where K=1/2mv^2. I solved K first and got 21,910,200. Then I solved p and got 41,340. Then I solved for wavelength using the de Broglie eq'n and got 1.604 x 10^-38, but this is not the correct answer. Where did I go wrong?? :grumpy: Thanks for your help!