Can lightening travel through house?

[pcdudedude]

If I have my computer completely unplugged. If lightening strikes can it travel out of the outlet, through the air and hit my computer anyway?

 

[Ubrales]

For a simple, cheap, and effective lightning arrestor, tie three knots on the power cord that runs from the computer to the outlet (Source: Tech article from Eaton Corp.)

To answer the OP's original question, NO. Once the device is unplugged from the wall outlet, lightning or any type of surge cannot travel through the electrical conductors. However, anything can be hit by a lightning strike, plugged, unplugged, or otherwise.

 

[synphul]

I would think most anything is possible. Luckily it hasn't damaged my pc, but I've had some concerning lightning strikes during bad storms. Not sure if 'strikes' is the right word since close by when lightning actually hits it makes a fantastic racket. Not really sure what it is, if it's the field from a lightning bolt or what but I have had 'inside lightning'. Best I can describe it. Lightning hits close and twice now I've had a bright blue/white ball of light _inside_ my room. Looks like a rapid flash of plasma and is bright enough to cause the eyes to flinch (similar to looking at a welding arc). Both times I felt a nasty sensation in my chest like a shock/heartbeat interruption.

On the bright side, no electronics were damaged 😛

 

[westom]

Lightning hits close and twice now I've had a bright blue/white ball of light _inside_ my room. Looks like a rapid flash of plasma and is bright enough to cause the eyes to flinch (similar to looking at a welding arc).

If that bright light was not from a flash through a window, then apparently lightning currents were inside a house. A strike to wires far down street can be a direct strike. A strike to nearby earth can also directly connect current through appliances to earthborne charges that are miles distant. Apparently that current did not find earth destructively via any appliances that time. Current may have been conducted by materials (ie linoleum, wood) you might not consider conductive. Protection inside appliances were sufficient then for lightning to connect to earth via some other and non-destructive materials.

Next time, does lightning have a connection to earth that remains outside? A properly earthed 'whole house' protector must exist to know. So that next time, protection inside appliances would not be overwhelmed.

If nearby strikes are that frequent (unusually often), then both appliance (whole house) and structure (lightning rod) protection is recommended.

 

[synphul]

Normally I'm not paying too close attention, other than notice the storm is rougher than usual. The strikes typically aren't 'that' close as in they're not directly in my yard. It's not a flash outside the window, the couple of times it's happened I don't even see a 'bolt' or anything like you typically see lightning from a distance. It's more of a really short and sudden buzz or hum and a welding arc is about the best way I can describe it. A concentrated 'ball' of intense blinding light with a radius roughly like that of a tennis ball. Only for a split second out of thin air and causes sensation similar to getting popped by an electric fence without getting a full jolt. The power doesn't go out or even flicker when it's happened. I've not noticed it in other rooms for whatever reason. Just a freak thing that's happened a couple of times over the past 10yrs.

There's a power pole about 20ft outside the window and it's grounded with solid copper wire/copper rod. It happens so fast it's hard to describe in better detail and catches you off guard. It can storm 40-50 different times or better and nothing happens then once it will happen. My guess is it's something residual from a strike, it's definitely not getting hit direct. Not as intense as standard house current, but stronger than a tens unit as if a really strong tens were applied to the chest and activated. Definitely gets my attention lol.

 

[westom]

It's more of a really short and sudden buzz or hum and a welding arc is about the best way I can describe it. A concentrated 'ball' of intense blinding light with a radius roughly like that of a tennis ball. Only for a split second out of thin air and causes sensation similar to getting popped by an electric fence without getting a full jolt.

You have described a reportedly rare phenomena called St Elmo's Fire. One report put that ball traveling down the aisle of a commercial airliner. Only speculation says what it is and why it occurrs. But others have reported similar events. In most cases, no damage reported.