हवा में यात्रा करने वाली ध्वनि तरंगों के संबंध में निम्नलिखित कथनों पर विचार कीजिए: 1. ये अनुदैर्ध्य तरंगें (Longitudinal waves) होती हैं। 2. ये अनुप्रस्थ तरंगें (Transverse waves) होती हैं। ऊपर दिए गए कथनों में से कौन-सा/से सही है/हैं?

Consider the following statements regarding waves: 1. If the particles of a medium move along the direction of propagation of the wave, the wave is called a longitudinal wave. 2. If the particles of a medium vibrate perpendicular to the direction of propagation of the wave, the wave is called a transverse wave. 3. Transverse waves involve changes in the shape/shear of the medium, whereas longitudinal waves involve changes in the density/volume of the medium. Which of the statements given above are correct?

At what speed should a source of sound move away from a stationary observer so that the observer perceives the apparent frequency to be half of the original frequency? (where v is the speed of sound)