group velocity

{
  "id": "NISTq117",
  "unitsml_id": "q:group_velocity",
  "name": "group velocity",
  "names": [
    {
      "value": "group velocity",
      "lang": "en"
    },
    {
      "value": "group speed",
      "lang": "en"
    }
  ],
  "short": "group_velocity",
  "type": "derived",
  "dimension": {
    "id": "NISTd11",
    "name": "velocity",
    "expression": "L·T-1",
    "components": [
      {
        "key": "length",
        "symbol": "L",
        "power": 1
      },
      {
        "key": "time",
        "symbol": "T",
        "power": -1
      }
    ],
    "dimensionless": false
  },
  "units": [
    {
      "id": "NISTu1.u3e-1/1",
      "name": "meter per second",
      "symbol": "m·s⁻¹"
    }
  ],
  "unit_count": 1,
  "identifiers": [
    {
      "type": "nist",
      "id": "NISTq117"
    },
    {
      "type": "unitsml",
      "id": "q:group_velocity"
    }
  ],
  "references": []
}