Simple Harmonic Motion (Person gets into car)

AI Thread Summary
An 85.0 kg person stepping into a 2400 kg car causes it to sink 2.35 cm on its springs, leading to a discussion on calculating the frequency of vertical oscillation. The spring constant k was derived using the equation mg = kx, resulting in k = 35483 N/m. The natural frequency of oscillation was calculated as ω = √(k/m), yielding a value of 3.78 Hz. However, it was clarified that this value represents angular frequency (ω), not the actual frequency. The relationship between angular frequency and frequency was also highlighted, indicating a need for further clarification on the calculations.
ThereIam
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An 85.0 kg person steps into a car of mass 2400 kg, causing it to sink 2.35 cm on its springs. If started into vertical oscillation, and assuming no damping, at what frequency will the car and passenger vibrate on these springs?



w= Sqrt (k/m), mg=kx, perhaps?



The way I treated the problem is with the assumption that the "If started into vertical oscillation" implied that the person/car began to oscillate from the new equilibrium position 2.35 cm below the old one. I then got the spring constant k by saying that 85*9.81 = k0.0235. Then I said the natural frequency of oscillation would be w= Sqrt(k/m) plugging in k = 35483 N/m and m = 2485 kg. Then answer I then got was 3.78 Hz. A problem I just did after this one suggests to me my thinking was wrong. Help please!
 
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Hi ThereTam, welcome to PF.
The answer you got is ω, not the frequency.
What is relation between ω and frequency?
 
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