Doppler effect

Question

Two cars, one in the front of the other, are traveling down the highway at 25 m/s. The car behind sounds it's own horn, which has a frequency of 500Hz. What is the frequency heard by the driver of the lead car? (Sound = 340 m/s)

Answer 1

According to doppler effect,

f' \(=(\frac{\nu+\nu_0}{\nu-\nu_0})f\)

where f = real frequency = 500 Hz

f' = apparent frequency

\(\nu\) = 340 m/s

\(\nu_0\) = 25 m/s

f' \(=(\frac{340+25}{340-25})\times500\)

f' = 365/315 x 500

f' = 579.365 Hz