My coworker was telling us this morning about how he used that trick where if you break off a light bulb trying to unscrew it, stick a potato on the broken part and unscrew it that way. Of course he was Mr. Safety and shut the light off before trying to change the bulb but he was wondering, if the fixture was turned on, if you’d get
shocked since a potato has so much water in it.
I said no because the thick dry skin of the potato would be an insulator. He says yes you would. Another coworker says no because a potato has too much starch and stuff to carry much of a current.
Who’s right (or all we all wrong :D) None of us are dumb enough to stick a potato into a live light socket to find out firsthand!
Too many variables for an accurate answer, but it would be risky to try. Electricians use insulation as a backup protection against shock - they turn the power off if they want to make sure they don’t get shocked.
My opinion is that the potato is a much better conductor than bare skin, so it would be a serious shock risk.
Shut off the light. A wet potato will create a short and blow the circuit breaker or fuse. Whether or not you feel a shock depends on the thickness of the skin.
I’m a licensed electrical engineer and my official answer is - I don’t know.
The potato’s inner core will definitely conduct electricity. In fact potatoes can be used as a gimmick battery to power small loads like clocks.
But the big trick is the skin. It might be sufficient enough to insulate you but it might not depending on how porous it is.
One thing to consider though is that squashing the inner potato into the base of a broken light bulb most probably would complete the broken circuit causing current to flow through the inner potato. Enough current in that wet environment could cause steam and a popped potato.
So, whether the skin protects you or not, sticking a potato into a hot socket is a really stupid idea.
The first rule of electrical safety is don’t assume anything. Check that switches are off, cords are unplugged, breakers are turned off, capacitors are discharged, and so on depending on what you’re working on.
Assuming that the skin of a potato is good enough insulation is the antithesis of this. In order to be sure you’d need to measure the conductivity of that specific potato in several different places just to get a rough idea. And then you still can’t be sure.
Like I said before, he did turn the power off before he changed the bulb, and none of us are dumb enough to try it with the power on, so I guess we will never know.
For a typically proportioned potato of roughly uniform flesh, I would expect the large majority of the current to flow from one bulb filament support to the other since they are pretty close to each other and would represent the lowest resistance. Some might flow from the hot filament to the bulb base, too. Almost none of the current should make it to the surface of the potato flesh and even less to get beyond the skin.
I happened to have an apple with me today and measured the resistance. The probes were about 3/4 inch apart and poked in about half an inch deep. Depending on the exact probe position, it was 40-60k ohms for about a quarter watt dissipated at 50k. That would slowly warm the apple. I’m not sure how well an apple compares to a potato for an electrical model, though.
All responses so far are missing the obvious: Jamming a potato into the socket is highly likely to tear the skin of the potato, as the sharp broken edges of the glass and metal stab into the potato.
Exactly.:smack:
I’ve used various vegetation (and other materials) to remove busted light bulbs, but the power was always off. YMMV depending on circumstance, but why risk it? I don’t put much stock in “maybes” when it concerns my life.
My dad had an Electrical Engineering professor in the 1940’s who could tell the difference between 110V and 220V by sticking his fingers into a socket. He had skin condition which made his skin dry. I suppose he probably could of used a potato on a live socket too…
