Find the total mechanical energy.

AI Thread Summary
The discussion revolves around calculating the total mechanical energy of a piston in simple harmonic motion (SHM) with a specified amplitude and frequency. The provided answer is 14 µJ, but participants express skepticism about deriving energy without knowing the piston's mass, as energy is proportional to mass. The formula for total energy in SHM is highlighted as 1/2 m ω² A², indicating that mass is a crucial factor. Participants are unable to find an alternative method to calculate energy without this information. The conversation emphasizes the importance of mass in energy calculations for SHM systems.
YMasoud
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Good day,
I found this question on the Web.

A piston in an engine moves back and forth over a distance of 2mm in SHM with a frequency of 120Hz. Find the total mechanical energy.

Is there a way to find the energy without knowing the piston's mass?
The answer provided is 14 \mu~J

Many thanks,
YMasoud
 
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I don't see how--the energy would be proportional to the mass (given fixed frequency and amplitude). Perhaps the mass is given elsewhere.
 
YMasoud said:
Good day,
I found this question on the Web.

A piston in an engine moves back and forth over a distance of 2mm in SHM with a frequency of 120Hz. Find the total mechanical energy.

Is there a way to find the energy without knowing the piston's mass?
The answer provided is 14 \mu~J

Many thanks,
YMasoud
I don't see how. The total energy is {1 \over 2} m \omega^2 A^2.
 
I've been looking for a way to do it without the mass and I can't see it...
 
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