Consider the Doppler effect in two cases. In | vedclass

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(B) For an observer moving towards a stationary source,the observed frequency is given by $n_1 = n_0 \left[ \frac{v + v_L}{v} \right]$.For a source mo

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more in the second case than in the first case.

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(B) For an observer moving towards a stationary source,the observed frequency is given by $n_1 = n_0 \left[ \frac{v + v_L}{v} \right]$.For a source moving towards a stationary observer,the observed frequency is given by $n_2 = n_0 \left[ \frac{v}{v - v_s} \right]$.Substituting the values $v = 330 \,m/s$,$v_L = 50 \,m/s$,and $v_s = 50 \,m/s$:$n_1 = n_0 \left[ \frac{330 + 50}{330} \right] = n_0 \left[ \frac{380}{330} \right] \approx 1.151 n_0$.$n_2 = n_0 \left[ \frac{330}{330 - 50} \right] = n_0 \left[ \frac{330}{280} \right] \approx 1.178 n_0$.Comparing the two results,we find that $n_2 > n_1$.Therefore,the frequency heard will be more in the second case than in the first case.

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