1. The problem statement, all variables and given/known data A vibrating string vibrates at 100Hz in oxygen.What is the frequency of its vibration in Hydrogen?[assume same temperature and pressure] 2. Relevant equations 3. The attempt at a solution Equating the velocities of sound gives 400Hz...But what pokes me is that the frequency is the property of the source.Will it change with ambient condition? In other words should not the answer be still 100 Hz?