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.
Question three is C and question 4 is b
We are given with a volume of a cube equal to 512 cm3. In this case, when the volume is expressed to cubic meters, the volume will still stay the same but the number of cubic units would decrease. a centimeter is a smaller unit than a meter, hence the value given should be divided by 1 million to express to m3.
Answer:
SI system i think it is right
Answer:
See explanation
Explanation:
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