MCQ
An observer starts moving with uniform acceleration $a$ toward a stationary sound source emitting a whistle of frequency $n.$ As the observer approaches source, the apparent frequency, heard by the observer varies with time as
- A
- ✓
- C
- D
✓
Answer
Correct option: B.
b
(b) For observer approaching a stationary source
(b) For observer approaching a stationary source
$n' = \frac{{v + {v_0}}}{v}.n$ and given ${v_0} = at$==>$n' = \left( {\frac{{an}}{v}} \right)\;t + n$
this is the equation of straight line with positive intercept $n$ and positive slope $\left( {\frac{n}{v}} \right)$.
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