MCQ
An observer starts moving with uniform acceleration $'a'$ towards a stationary sound source of frequency $f.$ As the observer approaches the source, the apparent frequency $f'$ heard by the observer varies with time $t$ as:
- ✓
- B
- C
- D
✓
Answer
Correct option: A.
a
For observer approaching a stationary source
For observer approaching a stationary source
$n^{\prime}=\frac{v+v_{0}}{v} n$ and given $v_{0}=a t \Rightarrow n^{\prime}=\left(\frac{a n}{v}\right) t+n$ This is the equation
of straight line with positive intercept $n$ and positive slope $\left(\frac{n}{v}\right)$
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