Any tips ?? Remembering formula

[Paddy4444]

Hey I’m studying 2365 at college and I’m at the science part now .. any tips on remembering formula or is it just a case of going over and over it till it’s in your head .. any help much appreciated

 

[Silly Sausage]

V=IR
I=V/R
P=VI
substitute I with V/R gives you ...
P=V * V/R = (V^2)/R

^2 is to the power of 2, ie V squared.

 

[Edtwozeronine]

Dropbox - Electrical Science.pdf - https://www.dropbox.com/s/69sr9tof37moj6p/Electrical%20Science.pdf?dl=0 Use this for walk throughs on all things electrical science.

 

[Deleted member 72666]

Some of you may find this useful when typing mathematical symbols.
Type mathematical symbols - online keyboard - http://math.typeit.org/

 

[Jay 1987]

V=IR
I=V/R
P=VI
substitute I with V/R gives you ...
P=V * V/R = (V^2)/R

^2 is to the power of 2, ie V squared.

I see what you’ve done, but I don’t understand what you’ve done!

What’s the need to substitute I for V

In what situation would you use V2?

 

[Richard Burns]

I see what you’ve done, but I don’t understand what you’ve done!

What’s the need to substitute I for V

In what situation would you use V2?

The variations in formulae are to account for the known variables.
On a piece of equipment designed for 230V ac if you use an ohmmeter to measure the resistance of the load then you now know two variables, R and V, if you want to know the power then you can use P=V²/R.
It would also be possible to get I from I = V/R and then use this calculated value for I in the P = VI equation but then you have to do two calculations.
Effectively you do the first calculation, I=V/R, in advance by substituting V/R for I in the P=VI equation.
Other versions of the equations can be used where you know different values.

 

[telectrix]

as richard burns said. if you know R but don't know I, then as above.

 

[Silly Sausage]

@stantheman

Cheers Stan

 

[Spunkywads26]

I am teaching electrical science at the minute with my students and have just covered ohms law, series, parallel, series+parallel and power.

I have found that it is easy for them to remember ohms law (V = I x R) and power formula (P = V x I). I then say that they can either remember the other 2 power formulas (P = I^2 x R & P = V^2/R) or if they can transpose and substitute formula then they only need the 1st two formula to work out the rest.

 

[telectrix]

this might be useful.:

 

[satori]

Hey I’m studying 2365 at college and I’m at the science part now .. any tips on remembering formula or is it just a case of going over and over it till it’s in your head .. any help much appreciated

Flash cards. That's what I used. Have a Google, there's software that lets you make your own. It helps having a buddy so you can each test each other. I found it worked very quickly. I can't remember any of them now - well, apart from Ohms Law, and power.

 

[delano]

Hey I’m studying 2365 at college and I’m at the science part now .. any tips on remembering formula or is it just a case of going over and over it till it’s in your head .. any help much appreciated

Learn transposition.

 

[telectrix]

Learn transposition.

the gender bender website will have all the info. .