The Diagram Shows Four Situations in Which a Source of Sound

question 36

Multiple Choice

The diagram shows four situations in which a source of sound S and a detector D are either moving or stationary. The arrows indicate the directions of motion. The speeds (when not zero) are all the same. (Note that the detector in situation 3 is stationary) . Rank the situations according to the apparent frequency of the source, lowest to highest.

• A) 1, 2, 3, 4
• B) 4, 3, 2, 1
• C) 1, 3, 4, 2
• D) 2, 1, 4, 3
• E) None of the above

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Definitions:

Louis Pasteur

A French biologist renowned for his discoveries in the principles of vaccination, microbial fermentation, and pasteurization.

Blood Type AB

A human blood group within the ABO blood typing system that has both A and B antigens on the surface of the red blood cells but no antibodies in the plasma.

RBCs

Red Blood Cells, also known as erythrocytes, are cells in the blood that carry oxygen from the lungs to body tissues and return carbon dioxide to the lungs.

Antigens

Substances, often foreign, that induce an immune response in the body, especially the production of antibodies.