Frequency of two objects moving toward eachother

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The discussion revolves around calculating the frequency heard by a motorcyclist as a police car approaches, with the police car emitting a sound at 502 Hz and moving at 27 m/s, while the motorcycle travels at 12 m/s. The initial attempt used an incorrect formula, leading to a frequency of 1631.5 Hz, which was identified as incorrect. The correct approach involves applying the Doppler Effect formula, specifically using the velocities of both the source and observer relative to the speed of sound. The correct calculation should yield a different frequency, but the final attempt resulted in an erroneous negative value. Clarification on the proper use of the Doppler Effect is needed for accurate results.
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Homework Statement



A motorcyclist and a police car are moving toward one another. The police car emits a sound with frequency of 502 Hz and has a speed of 27m/s. The motorcycle has a speed of 12 m/s.
What frequency does the motorcyclist hear?

Homework Equations



f=1/T
f'=f(1+v/vs)

The Attempt at a Solution



f'=502(1+27/12)
This gave me f'=1631.5 but it says this is incorrect
 
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I think your equations are wrong. According to the Doppler Effect, the apparent frequency ##n_a=(\frac{V+V_o}{V-V_s}) n##

## V ## is the velocity of sound.
 
so it would be
(27+343)/(12-343)*502
f=-561.15
 
read my post again.
 

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