prefer abbreviated units in model Properties?

[zepumph]

From #159, I know that in units.js it says to prefer abbreviated units. This would mean making the following changes to units passed to Properties in OhmsLawModel.js

• volts -> V
• milliamperes -> mA
• ohms -> Ω

@samreid does this feel like something I should do?

[samreid]

The rule of thumb we discussed with @pixelzoom is that the Property units should match what is shown in the user interface. So, using V, mA, A and Ω sounds good to me.

[pixelzoom]

Yep, agreed.

Should spend the time to do this project-wide? That would mean addressing these notes in units.js:

// NOTE: Abbreviations are preferred, see https://github.com/phetsims/phet-io/issues/530

// NOTE: In time, these will be replaced with abbreviations, see above.

[pixelzoom]

And I seem to recall that '\u2126' is preferred to 'Ω'.

[samreid]

I recall that consensus as well, though not the reasoning behind it.