Physics question stand alone

[MCAT guy]

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Is this a fair question?

The perception of sound waves is affected by the relative motions of the source and the receiver toward or away from each other. This phenomenon (also observed in light waves) is known as the Doppler effect. The relationship between the speed of a sound wave and its frequency for a moving source detecting a reflected wave off of a stationary object is expressed as: (doppler equation)

As the speed of the wave source (vs) decreases, we find that the:

The answer here was the frequency of the sound decreased but I had thought it increased... then I thought of why, I was thinking the source was moving away from the person, while in the solution it said the source was moving towards the person (or observer).

My question is, is this a fair question? Don't you have to define if the source is moving towards or away? I guess the equation they gave would make you think that it was toward but I wasn't necessarily thinking in their equation because I had memorized a variation of the equation.

their note said: "you should realize this is written for source moving toward the stationary object"

Shouldn't this have to be defined in the question?

 

[cbrons]

Which company gave you that question?

 

[MCAT guy]

Which company gave you that question?

Berkeley Review yo.

To be fair, they gave an equation alongside of the question... my problem is that the doppler equations people always write differently, so I didn't really want to use their equation (I had a slight variant memorized). The doppler effect people use +/- or only - or whatever, so I just understood the concepts.

Anywho, it seems like they should tell you what direction the source was moving. It is a FL question.