1. The problem statement, all variables and given/known data A man strikes a long aluminum rod at one end. Another man, at the other end with his ear close to the rod, hears the sound of the blow twice (once through the air and once through the rod), with a 332ms interval between them. How long is rod? 2. Relevant equations unsure about relevant equations. But because I think this might be open end air column or a closed end speed= frequency*wavelength (for open end) wavelength= (2/n)*Length (for closed end) wavelength= (4/n)*Length 3. The attempt at a solution At first I attempted this by doing v=x/t I assumed velocity of sound to be 340m/s, and the time .332s, so 340m/s *.332s= x = 112.8 but I got that wrong. Then I thought maybe I should treat this as an air column, but I can't figure out if this is a open end or closed end air column. I'm reading a section on these concepts but I'm just confusing myself even more. The aluminum rod is struck and the man on other end hears the sound once in the air but just once through the rod. What does this mean??