Puzzle. Electrical VS solid bar switch.

In summary, a long wire with no resistance can light an LED instantly. If the wire was 1,860,000 miles long, there would be a 10 second delay.
  • #1
4472
3
0
Good Evening,

I am not a science "professional" nor even a Physics Graduate. I am, however, interested in anything with a science twist. I have created an account on this forum hoping that someone can answer my puzzing question...

Start with the simplest circuit. Battery, switch, two wires and a bulb.
Switch on and the lamp lights.
For this puzzle, assume NO resistance in the wire and a bulb (LED or whatever) that has no resistance (so, to all appearances it lights istantly).

I realize that electron flow is slow 0.02cm / second?
However, effectively the speed of electricty is c (speed of light) or very near c.
So, if the wires were 186,000 miles long there would be a delay of 1 second between switch ON and light ON.
Additionally, a 1 second delay between switch OFF and light OFF.

If the wires were 1,860,000 miles long there would be a 10 second delay.
(all theoretical, of course. Hence assume NO resistance in the wires etc).

Now the puzzle:
In the circuit the wires are only 1cm long.
But... the entire circuit is 1,860,000 miles away.
There is a bar 1,860,000 miles long - this bar can be used to press the switch ON.
From 1,860,000 miles away you press the end of the bar.
The other end of the bar presses the switch ON.
The light comes on instantly.
NO 10 second delay...

Have we just transmitted a signal TEN times faster than the speed of light?

I think the line now is, "discuss"...

Hoping you can help and/or gives you all something to chat about over a beer or two.
Cheers
Darryl
 
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  • #2
4472 said:
From 1,860,000 miles away you press the end of the bar.
The other end of the bar presses the switch ON.
The light comes on instantly
Nope. The 'press'ure propagates throug the bar with the speed of sound.
 
  • #3
Interesting! But there are some thinhs I did not understand. How is the bar placed? Sorry I can't visualize. Wouldn't two such bars be needed(one in forward path and one in return path of the current)?
A diagram would be helpful.
 
  • #4
Ah ha, thank you BvU !
So, if the bar was 650 miles long (again, in space, no weight etc) and I moved one end 20cm, it would take an hour before the other end moved 20cm?

cnh1995
Only one bar - used to press the switch, and the switch is now 1,860,000 miles away. Imagine having a finger 1,860,000 miles long to press the switch.

Apologies, I have to go out. I'll check in here tomorrow.
 
  • #5
Done some more research - cheers BvU, answered my puzzle completey!

I'm off to see Star Wars :)
 

FAQ: Puzzle. Electrical VS solid bar switch.

What is the difference between an electrical switch and a solid bar switch?

An electrical switch is a device that controls the flow of electricity by opening or closing a circuit. It is typically made up of metal contacts that can be moved by a lever or button. A solid bar switch, on the other hand, uses a solid piece of metal to make or break a connection in a circuit.

How do electrical switches and solid bar switches work?

Electrical switches work by using an external force, such as a lever or button, to move metal contacts and create or break a connection in a circuit. Solid bar switches, on the other hand, use the physical movement of a solid piece of metal to make or break a connection in a circuit.

Which type of switch is more reliable?

It depends on the specific application. Electrical switches are more commonly used and are typically more reliable for everyday use. However, solid bar switches are often used in high-voltage applications and are considered more reliable in extreme conditions due to their solid construction.

Can a solid bar switch be used in place of an electrical switch?

In most cases, yes. However, it is important to consider the specific needs and requirements of the circuit before making a substitution. Solid bar switches may not be suitable for all types of circuits, so it is best to consult a professional if you are unsure.

Which type of switch is more cost-effective?

In general, electrical switches are more cost-effective due to their widespread use and availability. However, solid bar switches may be more cost-effective in certain high-voltage applications due to their durability and reliability.

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