2007-09-02 07:20:13 · 7 answers · asked by erik 1 in Science & Mathematics ➔ Physics
V = A/R
think of electricity as water being pumped through a pipe
voltage is the strength of the pump
amperage is the speed of the water
resistance is how skinny the pipe is
more voltage(stronger pump) then higher amperage(faster the water will flow)
more resistance(skinnier pipe) then less amperage (slower the water will flow)
this analogy is all you need
the end
.
2007-09-02 07:29:38 · answer #1 · answered by The Wolf 6 · 1⤊ 0⤋
You must understand the concepts of voltage, amperage and resistance as a basis for understanding.
Voltage is similar in concept to pressure.
Amperage is rate of flow.
Resistance is just that.
It takes a voltage (electrical pressure) to force the electrons through a circuit. This creates a current (measured in amperes, and similar to gallons per minute with fluids). The conductor doesn't like letting the electrons through, and resists the flow to a certain extent.
There is a relationship to the interaction of these three variables. Of course that is Ohm's Law. Mr. Ohm said that for a given set of conditions, that is, a voltage available and a specific resistance, a certain amount of current will flow. He expressed this relationship as follows:
The voltage will always be the current multiplyed by the resistance. Shorthand for this relationship is:
voltage = current times resistance. To further shorten this we use symbols for each. E or V for voltage, A for amperage (current) and R for resistance. We most often use E for voltage. I don't know why. Now we are down to E = I times R, or E = IR.
If we know any two of these, we can calculate the other. If you know the current and the resistance you can calculate the voltage by multiplying the two. E = IR
If we know the voltage and the current, we can calculate the resistance. R = E/I.
If we know the voltage and the resistance, we can calculate the current. I = E/R.
That shoul get you on your way.
2007-09-02 07:44:57 · answer #2 · answered by Ed 6 · 1⤊ 0⤋
Ohm's Law is a law relating to resistance, potential difference and electric flow. It is mathematically expressed as:-
Volts = Amps x Resistance
V = I x R
2007-09-02 07:26:07 · answer #3 · answered by lenpol7 7 · 1⤊ 0⤋
ohms law is the ratio between voltage (U), resistance (R) and amperes (I).
it is U = I * R
if you think about it, this makes perfect sense. lets pretend our wire is a hose, and the electricity is water.
The amperes is the amount of water that is moved
the resistance, is the width of the hose.
and the voltage is pressure.
if you have water running through the hose, and open the tap further, a bigger pressure builds up. this pushes more water through the same opening. the resistance (size of hte hose) stays the same, voltage (pressure) increases. so it pushes more amperes (water) through.
you can also get a bigger hose. which means the resistance would go down, (more water can pass through the hose at the same time), the amount of water to move stays the same, so the pressure needed to push the water goes down.
2007-09-02 07:23:57 · answer #4 · answered by mrzwink 7 · 1⤊ 0⤋
Ohms law is stated as follows;The current density in a circuit is directly propotional to the Electric field.
J = Sigma x E
To really understand it you need an electrical engineering degree.
2007-09-02 07:25:45 · answer #5 · answered by goring 6 · 0⤊ 1⤋
Ohm's law just defines relationships between Power, Current, Voltage, etc. He also got the resitance value named after him.
Here are some general equations.
Direct Current
AMPS= WATTS÷VOLTS
I = P ÷ E
A = W ÷ V
WATTS= VOLTS x AMPS
P = E x I
W = V x A
VOLTS= WATTS ÷ AMPS
E = P ÷ I
V = W ÷ A
For AC you just multiply the result by a Power Factor
2007-09-02 07:29:03 · answer #6 · answered by joel w 2 · 0⤊ 2⤋
maybe you should of went to school
2007-09-02 07:25:22 · answer #7 · answered by Anonymous · 0⤊ 0⤋