Problem 36P

A pipe in air at 20°C is to be designed to produce two successive harmonics at 240 Hz and 280 Hz. How long must the pipe be, and is it open or closed?

Solution 36PIntroductionFirst, we will calculate the required energy to increase the temperature from 25 to 30.Then we will calculate the time required to supply the required energy knowing the power.SolutionStep 1The energy required to increase the temperature is given byQ = mcTWhere m is the mass of the body, c is the specific heat and T is the change intemperature.Now the from the problem we know that m = 300 kgc = 3400 J/kg/KT = (30 25) = 5 = 5 KSo the required energy to be supplied is 6Q = (300 kg)(3400 J/kg/K)(5 K) = 5.1 × 10 J