Source: https://guthlabs.ai/docs/instruments/shaft-power-torque-speed-calculator/mechanism/

instrument mechanism / verified-clean

# Shaft Power-Torque-Speed Calculator mechanism

The inspectable method record for Shaft Power-Torque-Speed Calculator, kept separate from implementation and qualification.

Status: **VERIFIED_CLEAN**Lifecycle: **verified-clean**

## Model scope

The formula P = Tω = 2πNT/60 is standard and correct under the stated units. NEEDS_REVIEW is required because the ω output unit is not explicitly declared and the input mode ('P or T') does not specify behavior when both or neither are provided. The blank honest_label does not create a mathematical overclaim, but the user-facing label should state the input mode, output units, and zero-speed limitation.

No additional formula finding is recorded.

## Units and conventions

- N is rotational speed in revolutions per minute (rpm).

- T is torque in newton-metres (N·m).

- P is power in watts (W).

- ω is assumed to be angular velocity in radians per second (rad/s), although the output unit is not explicitly stated.

- The formula assumes consistent signed quantities; if magnitudes are intended, direction/sign conventions must be specified.

## Inspectable vector

One of 4 source-bound review vectors:

````
{
  "inputs": {
    "T_Nm": 50,
    "N_rpm": 1800
  },
  "expected_outputs": {
    "omega_rad_per_s": 188.49555921538757,
    "P_W": 9424.77796076938,
    "T_Nm": 50
  },
  "working": "ω = 2πN/60 = 2π(1800)/60 = 60π = 188.49555921538757 rad/s. P = Tω = 50 × 188.49555921538757 = 9424.77796076938 W."
}
````

## Failure boundary

**BREAK_CLAIMED** · SELF_FLAGGED

A nonzero power input at zero rpm produces a zero denominator when torque is calculated, so the instrument must reject the input or report torque as undefined rather than returning a finite value.

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/shaft-power-torque-speed-calculator/>)[03**Implementation**](<https://guthlabs.ai/docs/instruments/shaft-power-torque-speed-calculator/implementation/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/shaft-power-torque-speed-calculator/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche4/tranche4-results.json`

- `BOUNDARY_HAZARD_CATALOG.json`