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April 17[edit]

Laptop charger's 3rd prong broke off.[edit]

My laptop has 3 prongs and the 3rd 1 got cut and fell out. My laptop still recharges fine. Are there long-term disadvantages? My previous laptop has 2-prongs, why do some have 3? This appliance happens to be a laptop but I see it more of a science question. Thanks. 67.173.182.93 (talk) 11:51, 17 April 2023 (UTC).[reply]

The "third prong" I am guessing is the ground or earth wire, and you should not continue to use the plug. It will still operate, but the ground wire is an important safety feature that protects both you and your device. See here. I'm sure you can order a replacement charger, and should probably do so. --Jayron 32 12:10, 17 April 2023 (UTC)[reply]

Are you referring to the cable from the wall socket to the charger, or the cable from the charger to the laptop? If the former, Jayron32 has already answered, do not use it and get a replacement. If the latter it may be some form of communication between the laptop and the charger. Some manufacturers restrict non-proprietary chargers to a slower charge rate or not at all. Martin of Sheffield (talk) 13:24, 17 April 2023 (UTC)[reply]

I'd guess the earth prong was made of plastic, and it's purpose was to open the other slots. In which case be careful notr to touch the other prongs whilst plugging in the charger and you won't be able to use he charger with other plugs. You might have to use something like superglue to remove the prong from the socket. Don't stick in anything metal! NadVolum (talk) 16:06, 18 April 2023 (UTC)[reply]

I suppose the charger has the form of a little plastic box that sits directly over an outlet (a wall wart), with a low-voltage cord coming from it to reach the laptop. If so, then there is no real need for it to be grounded and it may have been built with a grounding (3-prong) plug because someone thought that was the correct standard to adhere to. However, if you have British-type electrical outlets then NadVolum's concern about "opening the other slots" would apply. --174.89.12.187 (talk) 22:04, 18 April 2023 (UTC)[reply]

Sorry for late reply, but yes I would say is the latter to Martin's question. Cable to laptop. But maybe I can extend this question to a simpler appliance in general, a 2-prong lamp vs. 3-prong lamp? What would the differences be? Thanks. 67.173.182.93 (talk) 02:07, 19 April 2023 (UTC).[reply]

If the lamp has metal parts that you can touch, they should be grounded to prevent a shock in case the wiring inside gets damaged. --174.89.12.187 (talk) 06:45, 19 April 2023 (UTC)[reply]

As explained already above in the first reply, the third prong provides grounding; see here. --Lambiam 06:58, 19 April 2023 (UTC)[reply]

Then how do laptops and appliances with only 2-prongs, do grounding? 67.173.182.93 (talk) 12:17, 19 April 2023 (UTC).[reply]

The simple answer is that they don't. Have a look at Appliance classes, in particular class II. In essence, if there is a possibility of exposed metalwork becoming live then the appliance has to be earthed (except in the USA). If there is no possibility of accessible parts becoming live, then it will be class II ("double insulated") and doesn't need earthing. If the item is totally isolated from the mains, such as a laptop, then it is class III and no safety earthing is required. Martin of Sheffield (talk) 13:47, 19 April 2023 (UTC)[reply]

Thoughtful non-blinking posture[edit]

Is there a name for condition when healthy people sometimes freeze for a few seconds in a thoughtful position, with their eyes not blinking and fixed at a random point? I suspect it's relatively common. 212.180.235.46 (talk) 18:06, 17 April 2023 (UTC)[reply]

Reflective pose? --136.56.52.157 (talk) 20:41, 17 April 2023 (UTC)[reply]

AFAIK reflective pose may involve facial changes and some other gestures. The one I'm interested has no movements at all, eyes not blinking and "frozen" as well, and typically occurs while sitting (this has been experienced by me and observed in other persons too). Possibly has something to do with relaxation. 212.180.235.46 (talk) 21:37, 17 April 2023 (UTC)[reply]

"in vacant or in pensive mood..." or "lost in thought"? Alansplodge (talk) 23:19, 17 April 2023 (UTC)[reply]

A different condition resembling this one is called here the "freeze response". This withdrawal freeze typically lasts much longer than this pensive freeze. The latter may serve to allow more mental processing resources to be devoted to producing a result. It is (at least according to my observations) mainly seen in a dialogue, when a respondent is trying to remember something or to find a good way to explain something. They may also grab their chin, but why? --Lambiam 09:13, 18 April 2023 (UTC)[reply]

Consider "petit mal" seizure or Catatonia syndrome. Philvoids (talk) 10:56, 18 April 2023 (UTC)[reply]

See also the thousand-yard stare, a symptom of battle fatigue. We also have an article called Blank expression. Alansplodge (talk) 12:57, 18 April 2023 (UTC)[reply]

Another possibility: White line fever. (WP:OR: had a couple of personal experiences with this phenomenon driving while sleep-deprived, and I can personally attest that a fixed stare is indeed one of the main symptoms of it!) 2601:646:9882:46E0:B06E:637E:D483:879D (talk) 02:58, 19 April 2023 (UTC)[reply]

I think petit mal, catatonia, the thousand-yard stare and white line fever all have nothing to do with the condition referred to in the OP, which may occur in the middle of the day to someone relaxed, awake and well, comfortably seated on a couch. --Lambiam 07:08, 19 April 2023 (UTC)[reply]

Lateral Eye Movements, according to various psychologists whose studies are mentioned here on the Naked Scientists podcast. Card Zero (talk) 02:51, 24 April 2023 (UTC)[reply]

Inducing this state for fun while crossing the road is called nerd sniping ;-) NadVolum (talk) 14:04, 24 April 2023 (UTC)[reply]