[wdestar]

I gave my students a little test.

Given: Voltage Source = 120 VAC. Load = 20 Amps. Transmission Line = 100' extension cord comprised of 16 gauge wires (not legal, of course), SO if you will.

Question: What voltage is available at the load?

We'll see what their answers are tomorrow.

 

[HackWork]

I see a bump in voltage drop smartphone app downloads tonight :whistling2:

 

[adamc]

That is easy. 0 volts...
My wife & daughter plugged in 13 toasters, 5 hair dryers and for good measure 2 curling irons... Breaker went 'pop'




Oh yes. AND they used several Dollar Store power strips also

 

[wdestar]

I see a bump in voltage drop smartphone app downloads tonight :whistling2:

Good point. Problem is, an app ain't gonna help them here.:thumbsup:

 

[wdestar]

That is easy. 0 volts...
My wife & daughter plugged in 13 toasters, 5 hair dryers and for good measure 2 curling irons... Breaker went 'pop'





Oh yes. AND they used several Dollar Store power strips also

Actually, when you visit Europe, sometimes troubles arise when you plug in 1 hair dryer.

 

[azgard]

Good point. Problem is, an app ain't gonna help them here.:thumbsup:

I can already see the wrong answer most of the students will put down, and it won't be that far off from the actual.

 

[wcord]

Good point. Problem is, an app ain't gonna help them here.:thumbsup:

Unless the extension cord is not plugged in then the voltage should 99.8 vac(16.8% drop)
Online app:thumbsup:

 

[wdestar]

I can already see the wrong answer most of the students will put down, and it won't be that far off from the actual.

Actually, it may be. I left out a lot of information that they need. But there is one answer that would be correct in all cases.

 

[wdestar]

Unless the extension cord is not plugged in then the voltage should 99.8 vac(16.8% drop)
Online app:thumbsup:

Not sure I agree with that... hmm...

 

[HackWork]

This is going to be something fu*tarded.

 

[azgard]

120-(20*(200*(4.016/1000)))= 103.936

13.39% drop

 

[wdestar]

120-(20*(200*(4.016/1000)))= 103.936

13.39% drop

You're getting the idea. But not quite there yet.

 

[wcord]

Not sure I agree with that... hmm...

http://www.electrician2.com/calculators/vd_calculator.html

and we all know the Internet doesn't lie:whistling2:

 

[wdestar]

http://www.electrician2.com/calculators/vd_calculator.html

and we all know the Internet doesn't lie:whistling2:

Just like the news media.

 

[Meadow]

Is this a trick question?

In reality 2 things are being left out, inductance of the transmission line and the resistance going up from heating which leads to more voltage drop.

 

[azgard]

I = 120/((120/20)+(200*(4.016/1000)))
I = 120/6.8032
I = 17.639A


Vd = 120-(17.639*(200*(4.016/1000)))
Vd = 14.168

V = 105.832
11.81% drop

 

[wdestar]

Someone Must Know

If you guys, the electricians, can't get this, I think my students will lose confidence in the whole process.

 

[Meadow]

If you guys, the electricians, can't get this, I think my students will lose confidence in the whole process.

Truth is your leaving a lot out. If you think vague questions get people to think your wrong.

 

[wdestar]

Is this a trick question?

In reality 2 things are being left out, inductance of the transmission line and the resistance going up from heating which leads to more voltage drop.

What does inductance have to do with anything? Your second point is quite valid.

 

[HackWork]

If you guys, the electricians, can't get this, I think my students will lose confidence in the whole process.

No, the truth is:

This is going to be something fu*tarded.