Explanation:
Given that,
Frequency of train horn, f = 218 Hz
Speed of train, 
The speed of sound, V = 344 m/s (say)
The speed of the observed person, 
(a) When the train approaches you, the Doppler's effect gives the frequency as follows :
(b) When the train moves away from you, the Doppler's effect gives the frequency as follows :
Hence, this is the required solution.
Answer:
D) diffraction
Explanation:
Corona is an optical phenomenon produced by the diffraction of sunlight or moonlight, as light moves through water droplets in the atmosphere.
This phenomenon produces one or more diffuse concentric rings of light around the Sun or Moon, usually seen as colored circles.
Therefore, the explanation for these phenomena of colored concentric circles, sometimes seen with the Sun or the Moon involves diffraction.
It can help with measurements and when you want to add measurements to a cylinder or a beaker so ya
It is made up of mostly water and salt. Cytoplasm<span> is present within the cell membrane of all cell types and contains all organelles and cell parts.
The cytoplasm is like a </span><span>bathtub water because it holds a kind of jelly fluid just like a bathtub
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eukaryote<span> is an </span>organism<span> with complex cells, or a single cell with a complex structure. </span><span>
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The type of radiation that can penetrate through paper, but not through wood is called beta rays. Beta rays can penetrate paper and air, but a thin piece of alimony can stop it. Gamma can cut through anything except lead and many inches of concrete. Alpha can be stopped by paper and not penetrated. The correct answer is B.
