College work ?

[Lee Kerr]

Hey Guys
im a 3rd year apprentice struggling with my college work anyone got a clue in this question
HELP ME! please

A coil of resistance 4ohms is connected across a shunt of resistance 0.005ohms if the current in the main circuit is 50a what is the current of the coil ? :sick:

 

[MarkieSparkie]

I don't think so! I'll stick with my previous answer.
Current Division Ratio
n = (R[SUB]shunt [/SUB]+ R[SUB]coil[/SUB]) / R[SUB]shunt[/SUB]
= (4 + 0.005) Ω / 0.005 Ω = 801
Coil Current
I[SUB]coil [/SUB]= I[SUB]supply[/SUB] / n
= 50A / 801
= 6.242197253 x 10[SUP]-2[/SUP] A
= 62.42 mA (62.4mA to 1 DP my previous answer QED)

 

[Knobhead]

Current = 50A
Rc = 4 Ώ
Rs = 0.005 Ώ
Is = Shunt current
Rp = Parallel resistance

1/(Rc+Rs) = Rp
1/(4+0.005) = 0.004994 Ώ

Rp*I = V
0.004994 *50 = 0.249688V

V/Rs = Is
0.249688/4 = 0.062422A

For mA
0.062422*1000 = 62.422mA

Is = 62.422mA

I hold my hand up Markie, I was wrong!

 

[Knobhead]

Forgive me?

 

[mechelec]

Does that mean I was right for a change.

 

[Knobhead]

Looks like another slice of umble pie for me.
Yes your right, I'm wrong. Bloody decimal points!
Can I have chips and gravy with the pie.

One thing it does show is there’s more that one way with questions to arrive at the same answer.

I notice our OP hasn’t come back.

 

[mechelec]

I suspect the OP has not come back because no one gave him an instant answer and told him how to do it although I could be wrong

 

[trev]

Mech you're such a cynic. The gadgie might be busy working the answer out

 

[Knobhead]

Can’t think why, he’s got both Markies and my answers.
You can’t get better proof than two different calculations with the same answer.
But he really should do his own homework.

 

[mechelec]

Mech you're such a cynic. The gadgie might be busy working the answer out

Age makes you cynical

 

[Lee Kerr]

Thanks for all the help guys this question has blown my brain to bits hahaha i get all of the working out but how did u know how to do it

(Rc+Rs)/Rs=N
(4+0.005)/0.005=801
Ic = Is/N
50/801 = 0.0624
0.0624 x 1000 = 62.4mA

 

[trev]

Age makes you cynical

Dead right mate, I used to be easy going