3 ms·

Terawatt-miles. A unit of measurement I'm glad to have been exposed to today.

by quantified 3y ago

klysm 3y ago
If a watt is 1 kg⋅m2⋅s−3, and we multiply by distance we get 1 kg⋅m3⋅s−3. I wonder what that means
- westurner 3y ago
  Here's that with Pint for Quantities and Units with `%pip install -q` for Jupyter notebooks with e.g. Google Colab or vscode.dev+pyodide or JupyterLite or ... in Jupyter notebook Percent format with the %%ipytest cell magic function to upgrade test assertions (and @pytest.fixture s) and run everything starting with test_ with the pytest test runner: # %% %pip install -q pint ipytest pytest-cov import ipytest ipytest.autoconfig() # %% %%ipytest -v # --help def test_pint_units_for_watt_meters(): import pint ureg = pint.UnitRegistry() unit1 = ureg.kilogram*(ureg.meter**2)*(ureg.seconds**-3) unit2 = unit1 * ureg.meter assert 1*unit1 == 1*ureg.watt assert 1*unit2 == 1*ureg.watt*ureg.meters
- quantified 3y ago
  This is where simply multiplying the units through can be misleading as it hides semantics. The distance/area of m in the watt is not necessarily the same as the distance of the m in the length of conductor. But an interpretation would be volume which seems intuitive, double the length or area of a cylinder and you double its volume.
  - westurner 3y ago
    So there are three parameters; watts, conductor_path_length, and watt_meters?
    - hulitu 3y ago
      https://en.m.wikipedia.org/wiki/Transmission_line https://en.m.wikipedia.org/wiki/Transmission_line
      - westurner 3y ago
        Transmission line > Matrix parameters > Variable definitions: https://en.wikipedia.org/wiki/Transmission_line#Variable_definitions https://en.wikipedia.org/wiki/Transmission_line#Variable_def... But, FWIU how this applies to line length and transmission time hadn't been tested until Veritasium's experimental video with CalTech with like a mile of cable: https://youtu.be/oI_X2cMHNe0 https://youtu.be/oI_X2cMHNe0 So, it doesn't need multiple length parameters.
- bobbylarrybobby 3y ago
  Don't get me started on the spring constant...

Terawatt-miles. A unit of measurement I'm glad to have been exposed to today.

klysm 3y ago

If a watt is 1 kg⋅m2⋅s−3, and we multiply by distance we get 1 kg⋅m3⋅s−3. I wonder what that means

westurner 3y ago
Here's that with Pint for Quantities and Units with `%pip install -q` for Jupyter notebooks with e.g. Google Colab or vscode.dev+pyodide or JupyterLite or ... in Jupyter notebook Percent format with the %%ipytest cell magic function to upgrade test assertions (and @pytest.fixture s) and run everything starting with test_ with the pytest test runner: # %% %pip install -q pint ipytest pytest-cov import ipytest ipytest.autoconfig() # %% %%ipytest -v # --help def test_pint_units_for_watt_meters(): import pint ureg = pint.UnitRegistry() unit1 = ureg.kilogram*(ureg.meter**2)*(ureg.seconds**-3) unit2 = unit1 * ureg.meter assert 1*unit1 == 1*ureg.watt assert 1*unit2 == 1*ureg.watt*ureg.meters
quantified 3y ago
This is where simply multiplying the units through can be misleading as it hides semantics. The distance/area of m in the watt is not necessarily the same as the distance of the m in the length of conductor. But an interpretation would be volume which seems intuitive, double the length or area of a cylinder and you double its volume.
- westurner 3y ago
  So there are three parameters; watts, conductor_path_length, and watt_meters?
  - hulitu 3y ago
    https://en.m.wikipedia.org/wiki/Transmission_line https://en.m.wikipedia.org/wiki/Transmission_line
    - westurner 3y ago
      Transmission line > Matrix parameters > Variable definitions: https://en.wikipedia.org/wiki/Transmission_line#Variable_definitions https://en.wikipedia.org/wiki/Transmission_line#Variable_def... But, FWIU how this applies to line length and transmission time hadn't been tested until Veritasium's experimental video with CalTech with like a mile of cable: https://youtu.be/oI_X2cMHNe0 https://youtu.be/oI_X2cMHNe0 So, it doesn't need multiple length parameters.
bobbylarrybobby 3y ago
Don't get me started on the spring constant...