KVPY Sample Paper KVPY Stream-SX Model Paper-23

A source of frequency 'f' is stationary and an observer starts moving towards it at \[t=0\] with constant small acceleration. Then the variation of observed frequency f' registered by the observer with time is best represented as:

A)

B)

C)

D)

Correct Answer: A

Solution :

After a time t, velocity of observer \[{{V}_{0}}=\text{at}\]

\[\therefore \] \[{{f}_{0}}=\left( \frac{V+{{V}_{0}}}{V} \right){{f}_{s}}.\] \[=\left( \frac{V+\text{at}}{V} \right){{f}_{s}},\]

which is a straight line graph of Positive slope.