Hello all, 1. The problem statement, all variables and given/known data A vibrating string 50.0 cm long is under a tension of 1.00 N. The results from five successive stroboscopic pictures are shown. The strobe rate is set at 5000 flashes per minute, and observations reveal that the maximum displacement occurred at flashes 1 and 5 with no other maxima in between. (a) Find the period, frequency, and wavelength for the traveling waves on this string. EDIT: (b) How fast is point P moving when the string is in position 3? 2. Relevant equations * A wave pattern travels with constant speed a distance of one wavelength λ in a time interval of one period T. f=1/T λ=v/f v=ωk ω=2[itex]\pi[/itex]/T k=2[itex]\pi[/itex]/λ 3. The attempt at a solution My main concern is regarding the period -- I understand how to compute the other values thereafter. I am a little unclear as to why certain values are used in computing the period. For instance, we are given that over 60 seconds, 5000 flashes occur, therefore 60/5000. Then, in the solution, that value is multiplied by 4. I'm having a hard time conceptualizing why the number 4 is used as oppose to 5, especially since the picture depicts 5 different moments in time. From that point, once I have that value, I would assume it to consequently be the period, as that is the amount of time for one wavelength to occur. This is incorrect, however, though I don't understand why. Really just having a hard time conceptualizing some little things before I can progress with the question. Any help would be greatly appreciated. EDIT: For part b, I set v=kω. Using k=2[itex]\pi[/itex]/λ I solved for k, and I solved for ω using ω=2[itex]\pi[/itex]/T and then multiplied the two values together to solve for v, however I'm getting an outrageously high velocity, and I don't believe it is correct. Also, my method doesn't take into account the displacement from the amplitude of 1.5cm, though I'm not sure how to take it into account in this instance. Thank you!