easy way to remember electric equations?

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Terp

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I been studying my ARRL Ham radio license manual. I'm having trouble with remembering the electric parts like voltage, ohm, current, amps etc. is there a easy way to remember these? thanks
 

1hogrider

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I been studying my ARRL Ham radio license manual. I'm having trouble with remembering the electric parts like voltage, ohm, current, amps etc. is there a easy way to remember these? thanks

Easy way to remember Ohms law-
E
-----------------
I | R

Just cover up the value you are trying to solve. If you want to solve for voltage (E) simply multiply current (I) X Resistance (R). If you want to solve for Current (I) divide voltage (E) by resistance.

If you can't remember which letter goes where, remember the word "Eagle" starts with the letter "E" so it would go high.
 

fmon

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A pie formula is the Navy method. Draw a circle with a horizontal line splitting the circle in two halvs. Draw a versicle line from center of previous line to lower part of circle. This is a pie with 2 parts quartered and one part halved.

Place an E on top for Voltage (EMF). Place and I for Current on left of versicle line. Place an R for resistance on right side of versicle line. The horizontal line is a divider and the versicle line is a multiplier.

E=IR is the formula.

For power, use same method but replace the letters with P=IE.
 

gmclam

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There are a lot of different formulas, but many are just the same equation stated differently. So learn just one of each of the variations.

Someone used voltage (E) equals current (I) times resistance (R) earlier; or E= IR. So that can tell you E/I = R or E/R = I.

Do the same thing for power; P = E times I or ......

Are there specific equations you are having trouble with?
 

Nubz

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There are a lot of different formulas, but many are just the same equation stated differently. So learn just one of each of the variations.

Someone used voltage (E) equals current (I) times resistance (R) earlier; or E= IR. So that can tell you E/I = R or E/R = I.

Do the same thing for power; P = E times I or ......

Are there specific equations you are having trouble with?
sort of what i did replacing the E I and R with what they stand for

V..voltage C...Current the R is resistance so it didn't confuse me and i left it the same
this could confuse some but it got me to remember the E I and R what each stood for
 

Nubz

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E = electromotive force or voltage, not V.

I = current in amps.
umm no

Voltage in a circuit is Voltage (E) equals current (I) multiplied by resistance (R) [E=I × R].
Current in a circuit is Current (I) equals voltage (E) divided by resistance (R) [I=E ÷ R].
Resistance in a circuit is Resistance (R) equals voltage (E) divided by current (I) [R=E ÷ I].
copied right out of my study guide
 

dd364

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The effect is equal to what caused it divided by what opposes it. I=V/R The current is the effect.The voltage is what made it and the resistance is what trys to stop it.This formula comes up a lot in science and technology in different forms such as a=F/m (acceleration=force/mass).If you learn to think of it like this instead of just remebering it it will help you out in the long run.
 

dd364

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also E means it's the source such as a battery.V means it's a voltage drop such as across a resistor.The math is the same.
 

Terp

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What formula is used to calculate current in a circuit?
Current (I) equals voltage (E) multiplied by resistance (R).
Current (I) equals voltage (E) divided by resistance (R).
Current (I) equals voltage (E) added to resistance (R).
Current (I) equals voltage (E) minus resistance (R).

I have trouble remembering formulas like this. thanks
 

Terp

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how would you go about finding correct answear.

How much power is being used in a circuit when the voltage is 120 volts DC and the current is 2.5 amperes?
1440 watts.
300 watts
48 watts
30 watts
 

zz0468

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how would you go about finding correct answear.

How much power is being used in a circuit when the voltage is 120 volts DC and the current is 2.5 amperes?
1440 watts.
300 watts
48 watts
30 watts
The equation (or one of them) for power is voltage X amperage = watts.
 

fmon

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how would you go about finding correct answear.

How much power is being used in a circuit when the voltage is 120 volts DC and the current is 2.5 amperes?
1440 watts.
300 watts
48 watts
30 watts
As in post #4, P=IE
 

Sccafire

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What formula is used to calculate current in a circuit?
Current (I) equals voltage (E) multiplied by resistance (R).
Current (I) equals voltage (E) divided by resistance (R).
Current (I) equals voltage (E) added to resistance (R).
Current (I) equals voltage (E) minus resistance (R).

I have trouble remembering formulas like this. thanks
With this question here you can eliminate 2 answers right off the bat. You will never add or subtract anything to fiqure out the answer.
 

ampulman

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With this question here you can eliminate 2 answers right off the bat. You will never add or subtract anything to fiqure out the answer.
There's an even easier way to remember. You don't have to memorize anything and risk getting it wrong. Just learn the basic equation: I equals E over R.

Visualize an equilateral triangle and label the upper apex as E. The lower-left labeled as I; the lower right labeled as R. Then looking at the triangle and the position of the labels, I (lower-left) = E (upper) over R (lower-right). E (upper) = I (lower-left) * R (lower-right). R (lower-right) = E (upper) over I (lower-left).

Amp
 
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