Why does the doctor place the stethoscope on several different places of your chest to listen to your heart beat?

Answer 1

Because he's also listening to the left & right ventricles as well to listen for possible restrictions. Your heart is intrinsically a pump if you will, and the ventricles or venting tubes might be considered like hoses. Well if the 'hoses' are getting built-up inside with restrictive materials it will cause the 'pumping'- pressure to build-up. Since the 'pump' pumps at a predetermined rate or at a continuous pressure a restriction would slow-down the flow, hence a pressure build-up. When and if that happens it will have damaging effects on the entire body that will eventually lead to a heart-attack and even death! Our bodies must have a steady and regulated supply of that precious fluid known as Blood. Its just how we were created. Too many a big mack can lead to a heart attack...Jack. So be cool & careful.