Two pipes, equal in length, are each open at one end. Each has a fundamental frequency of 473 Hz at 297 K. In one pipe the air temperature is increased to 302 K. If the two pipes are sounded together, what beat frequency results? I think I missed this day entirely due to another project. I know that when you have two frequencies, you cannot simply add them together. It also says "one pipe" but not which one? Apparently, it doesnt matter, but I don't see how you;d know when to use the formula Vair = 331 m/s * sq. rt. of (T/273). thanks for any help!