Windshield Wipers

[Lord Popgun]

Well she has that down but I meant the right/left hand rule for motors/generators.

Az bob. What she is showing is--if you gripped a conductor so you fingers point in the direction of the magnetic field, your thumb will point in the direction of current flow. Or if you knew current direction it would show magnetic field direction.

If I had ever bothered to learn to post pics, I'd show the ones I'm talking about. But if you point your thumb up, and forefinger straight, and the finger under that at a right angle to it. Shows the relationship of current direction, magnetic field direction and motion of the rotor, or dirction of current flow if a generator. Its best to just google it as you can see some pics.

In the class project, it would be easy to hold your hand in the correct position and see that it actually works!

[Greg_imp]

Yeah, but coat hangers are part of HER domain (I don't mean my daughter). She never goes near windshield wipers or the man cave in my garage. Besides, I don't think a coat hanger would work nearly as well in the hand grip situation or the motor brushes. They're coated with laquer which I wouldn't want in my gasoline.

The right hand rule: current passing through a wire produces a magnetic field around it. Hold your right hand out, palm down. Extend your thumb. The thumb points in the direction of current travel - from positive to negative - and the curling fingers correspond to the direction of the magnetic field from positive to negative around the conductor.

[The Spaceman_imp]

Very clever, thanks for sharing!


Sent from my iPhone using Tapatalk

What he said.

Sent from my Android using my nose-picking finger.

[AzBob_imp]

Yeah, but coat hangers are part of HER domain (I don't mean my daughter). She never goes near windshield wipers or the man cave in my garage. Besides, I don't think a coat hanger would work nearly as well in the hand grip situation or the motor brushes. They're coated with laquer which I wouldn't want in my gasoline.

The right hand rule: current passing through a wire produces a magnetic field around it. Hold your right hand out, palm down. Extend your thumb. The thumb points in the direction of current travel - from positive to negative - and the curling fingers correspond to the direction of the magnetic field from positive to negative around the conductor.

Lol.

Quote:Besides, I don't think a coat hanger would work nearly as well in the hand grip situation or the motor brushes. They're coated with laquer which I wouldn't want in my gasoline.
True enough, which is why I said "most." I only brought it up because wire hangars are usually a lot more accessible than the piece you mentioned, however, I think that's an excellent use. I honestly can't remember the last time I changed the wiper blades on any of my vehicles, though (I live in the desert).

Yeah, but coat hangers are part of HER domain (I don't mean my daughter). She never goes near windshield wipers or the man cave in my garage. Besides, I don't think a coat hanger would work nearly as well in the hand grip situation or the motor brushes. They're coated with laquer which I wouldn't want in my gasoline.

The right hand rule: current passing through a wire produces a magnetic field around it. Hold your right hand out, palm down. Extend your thumb. The thumb points in the direction of current travel - from positive to negative - and the curling fingers correspond to the direction of the magnetic field from positive to negative around the conductor.

Electrical current flows from the negative terminal to the positive terminal.

[Greg_imp]

Ha, Bob. To be technically correct I think you have to say "electrons flow from negative to positive". To the great confusion of people trying to learn this stuff, "conventional" current flow is from positive to negative. Also, holes flow from positive to negative, but this is only really used in semiconductor theory.

So does lightning strike up or down?

[Lord Popgun]

Greg, I was in and currently work for the Navy. The Navy teaches that electrons are the charge carriers and since they are are negative current flow is negative to positive.

And like you said, holes flow in simiconductors, not wires. The Navy doesn't teach it as well as they used too, so I get to bone up on it every now and again to refresh the shop techs. Some don't even know how diodes work...

[Ridem32_imp]

Diodes are like a one way street lol

[Lord Popgun]

Ridem,

Oh yeah, they get that, its HOW they accomplish that...

Next up, quarter wavelength stubs/duplexer operation. One guy said "get the (blank) out of here!" I had to refer him to a training manual...

[rboe]

http://www.mi.mun.ca/users/cchaulk/eltk1...e/ivse.htm

Most cloud to ground lightening strikes go from the cloud to the ground. Typically a leader will rise up from the ground shortly before the main lightening bolt hits to meet it. I'm not aware of any human eye quick enough to see this though.

Once the bolt hits, there is an exchange of current that pulses up and down the bolt a few times before it winks out.

Lightening bolts come in many different power levels from cold to hot (starts fires) up to super bolts. Super lightening strikes can reach inside ANY man made structure. One was responsible for a weapons depot destruction in WW11 on the Allied side in the Pacific. Another, a super secret Soviet bunker went up and was blamed on lightening.

http://www.youtube.com/watch?v=a4Kkjm9J3vI

http://www.forte.lanl.gov/science/public...nation.pdf

So I'll add that perhaps wiperblade cores could be used as lightening rods.........