Need help answering (21) A student is given a long cylindrical tube that is open at both ends. The student is also given a sound wavegenerator that is set to a fixed but unknown frequency. The student activates the sound wave generator and thenholds it above the tube, which has been lowered into a tub of water. The tube continues to be lowered into the wateruntil the sound that is observed is at a maximum volume level. The student observes that this phenomenon occurswhen the distance L from the top of tube to the water level is 15.0 centimeters. At this position, a standing wave isestablished in the tube, as shown in the figure below.Sound WaveGeneratorL = 15 cm10 cmThe antinodes of the figure represent the maximum displacement of air within the tube.A student takes a second sound wave generator and places it above the open end of the tube so that it producessound at the same frequency as the first wave generator. Both sound wave generators emit sound such that thesound waves are in phase. Which of the following claims is correct about how the standing wave inside the tubechanges?(A) The wavelength of the resulting standing wave increases(B) The speed of the resulting standing wave inside the tube increases(C) The frequency of the resulting standing wave increases(D) The energy contained in the resulting standing wave increases

When two waves of same frequency travel in same direction they tend to interfere with each other.…

(21) A student is given a long cylindrical tube that is open at both ends. The student is also given a sound wave generator that is set to a fixed but unknown frequency. The student activates the sound wave generator and then holds it above the tube, which has been lowered into a tub of water. The tube continues to be lowered into the water until the sound that is observed is at a maximum volume level. The student observes that this phenomenon occurs when the distance L from the top of tube to the water level is 15.0 centimeters. At this position, a standing wave is established in the tube, as shown in the figure below. Sound Wave Generator L = 15 cm 10 cm