Naw! Common sense should be common which is why it's called common sense...
I would use meter and second.
Hope this helps.
I think it’s the first one
Answer:
The value is 
Explanation:
From the question we are that
The velocity 
The time taken is 
The total mass of the train is 
Generally the average power delivered is mathematically represented as
=> 
=>
Answer:
Explanation:
Speed of the source of sound = v = 44.7 m/s
Speed of sound = V = 343 m/s
a) Apparent frequency as the train approaches = f = [V /(V -v) ] × f
= [343 / (343 - 44.7) ] × 415 = 477.18 Hz
Wave length = λ = v / f = 343 / 477.18 = 0.719 m
b) Frequency heard as the train leaves = f ' = [V / ( V + v) ] f
= [343 / { 343 + 44.7 ) ] x 415
= 367.2 Hz
Wavelength when leaving = v / f = 343 / 367.2 = 0.934 m
