User suggestion: conventional current direction

[oliver-phet]

Can I suggest that you have the current go in the conventional direction, not the direction that the electrons flow? Or maybe allow the user to choose... Current: flow of electrons or conventional positive current.

[arouinfar]

I would be in favor of this change, as it would add a bit more flexibility to the sim, but doesn't seem overly complicated. We could add a radio group for electrons/conventional underneath the current direction checkbox, similar to our approach in CCK.

Here's a comparison of the electron and conventional current direction arrows, with the conventional current arrows being a semi-transparent RED_COLORBLIND.

If we decide to make this change, it seems appropriate to tack onto #234. @ariel-phet what do you think?

[ariel-phet]

@Denz1994 is going to start working on this issue, and will consult @arouinfar as needed

[arouinfar]

@Denz1994 I realize the current direction isn't ready for review, but while reviewing #234, I noticed that the current direction is broken. The top and bottom arrow both point in the same direction, rather than completing the circuit.

master (top arrow correct):

published version:

[Denz1994]

Thanks for the catch @arouinfar. Commit https://github.com/phetsims/capacitor-lab-basics/commit/85dbf1293ba206068ac5a051c074ab4e86647514 should have corrected the same-sided orientation you mentioned above.

Can you review the current status of master to assure the behavior is correct with the radio button selection?

Also do we only want these options on the lightBulbScreen?

[arouinfar]

@Denz1994 the behavior is now for correct for both current direction options.

Also do we only want these options on the lightBulbScreen?

No, it should be on both screens. Thanks for checking!

[arouinfar]

@Denz1994, while I'm reviewing things, here are some pixel polishing suggestions. I realize these may be things you simply haven't gotten to yet, but I just want to make sure we're on the same page.

• [x] Conventional current arrow should have a + in the middle
• [x] Electrons/Conventional radio group should be left-aligned with "Current Direction".
• [x] The panel width (and the toolbox on Light Bulb) should probably be 10% wider. It's looking a little crowded.

[Denz1994]

@arouinfar Please review master for the above changes, especially the behavior for switching current direction. Thanks.

[arouinfar]

@Denz1994 everything's looking good!

[Denz1994]

Thanks, @arouinfar closing this issue.

[arouinfar]

@Denz1994 since this feature isn't yet deployed (see #237), I'm going to reopen but leave unassigned.

[Denz1994]

The panel width (and the toolbox on Light Bulb) should probably be 10% wider. It's looking a little crowded.

I added an alignGroup option for the right side panels. This should make i18n compatibility a lot smoother. @arouinfar Please confirm the panel sizes still look good on master.

[arouinfar]

@Denz1994 the wider panel is nice, but there's far too much padding to the left of the checkboxes. Perhaps the strings have been accidentally centered?

The left padding in the published version is preferred:

[arouinfar]

@Denz1994 I'm also noticing that the panel width is inconsistent across screens.

Capacitance:

Light Bulb:

[Denz1994]

@arouinfar Please review master for above changes.

[arouinfar]

Looks great!

[Denz1994]

Great, this should make i18n a lot easier.

[arouinfar]

@Denz1994 I've noticed that the current direction doesn't revert to Electrons on reset all, as it should. This is present in master and the latest dev.

[Denz1994]

@arouinfar Good catch. Solution pending.

[arouinfar]

Great, @Denz1994! Can you publish a new dev version when it's addressed? I discovered the bug in #235, and it would be nice to have an updated version for primer recording.

[Denz1994]

@arouinfar Please review master for above reset correction. Once reassigned to me I will push a dev version.

[arouinfar]

Looks good @Denz1994!

[Denz1994]

Dev version pushed here. @arouinfar

[arouinfar]

Thanks!

[arouinfar]

Not quite a suggestion, but a user emailed phethelp in regards to the current direction, and the solution would be the conventional current representation.

In reference to the capacitor labs, while charging/discharging the capacitor an arrow displays indicating the current. I read the Help document and it states that arrow represents the direction of the current but not the magnitude. I have attached a screenshot of the capacitor discharging through the light bulb. However, it looks to me like the arrow is representing the direction of the electron flow, which is the opposite direction of the electric current. The classical electric current assumes positive charge carriers (incorrectly), so the direction of the current flow should be clockwise through this circuit, while the electrons flow counterclockwise. I think the simulation is intending to show the electron flow, rather than the current because there is also a negative sign on the arrow. Am I correct in my assumption that the simulation is showing the direction of the electrons? If so, why is called the current?

I replied to the user to let them know we are working on a conventional current representation, and that the sim will eventually be republished with the feature.