Maths - Inductance and capacitance: Advanced

[D Skelton]

Here's a nice little juicy one to get your teeth in to

 

[Happy Jack]

Neglecting my efforts on this here forum. Poor Sintra and his traffic light, I do apologise if he reads this. I've been a little pre-occupired with work at the moment; I had to rewire my first 3036 fuse this week. Given the rarity of such encounters I considered it something of a novelty.

Anyway, once more thanks for the efforts Mr. D. I'll have to retrieve my notes for this one once I've had one of Scaddens apparent pints. Or is it a true pint? I forget...

 

[Baker1988]

Hi i have not done inductance or capacitance at college yet so i would not know where to start so i will just sit back and read what every one else answers and try to learn how to do this

 

[Martyc]

I'd have to break the notes out too to suss this out not something I remember overly well as yet

 

[D Skelton]

C'mon Archy, I need some help to inspire these youngsers!

Trying to sell maths as 'cool' is like trying to get blood out of a stone!

Anyone gonna have a pop? ANYONE???

 

[Marvo]

Selling maths as anything is a tough one. Surely one of the students can make a start, resolving the resistors into a single resistance is an easy first step.

 

[Silly Sausage]

Selling maths as anything is a tough one. Surely one of the students can make a start, resolving the resistors into a single resistance is an easy first step.

I managed to work out the source V out earlier, then got distracted!

 

[D Skelton]

Bump

 

[jimmyray]

Hi mate, spent a fair bit of time with this one. My answer would be that A should be a resistor of value 368.49 Ohms to provide a power factor of 0.90. I think I'm pretty confident with this one, as have been grappling with my calculator to check it. I look forward to hearing from you. Cheers J

 

[D Skelton]

Way out buddy

Lil tip, you wouldn't use a resistor to correct power factor.

 

[jimmyray]

Aargh! Back to the drawing board!!

 

[jimmyray]

Just to check I'm going in the right direction, is the power factor initially 0.98 before trying to correct it? As this is what I've calculated so far.

 

[D Skelton]

No, as in any real life situation you are always trying to achieve unity or at least close to it. Sometimes allowances are made so that you don't tip the other end of the scale and as such you will find a selectable value on all PFCUs. This is a value you can choose to correct the PF to.

In this example, the existing PF is lower than the value I ask for it to be corrected to.

I can't think of any case where you would want to achieve a lower power factor

 

[jimmyray]

Fair point. To be honest we haven't started this stuff at college, so I may be trying to run before I can walk.

 

[D Skelton]

That's ok, show your working out and I'll see if I can help guide you in the right direction