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Energy against time runs at 2f
● VERBATIM — examined word-for-wordKE and PE each oscillate at frequency 2f — the particle hits max speed twice per cycle. The energy graphs are NOT at f.
What this actually means
The mass passes through maximum speed twice per cycle, once in each direction, so kinetic energy peaks twice per cycle. The energy graphs therefore oscillate at 2f.
Sketch marks hang on two facts: energy curves are never negative, and they run at double the displacement frequency.
The trap
Drawing energy–time graphs at f instead of 2f.
Prove it — watch it be true
- Watch one full swing of the mass
- Count the KE bar's peaks: two per oscillation
- Twice the peaks means twice the frequency: energy runs at 2f