Register to reply 
Voltage, Current, Resistance Relationship 
Share this thread: 
#1
May2208, 02:50 AM

P: 206

So I know [itex]V=IR[/itex] but can someone tell me which elements are proportional to each other?
...I believe current in inversely proportional to resistance but what about current and voltage. Also, what about voltage and resistance? 


#2
May2208, 02:57 AM

Emeritus
Sci Advisor
PF Gold
P: 9,772

[tex]x = k\cdot y[/tex] Where k is the constant of proportionality. When we say x is inversely proportional to y, we can write it in this form, [tex]x = \frac{k^\prime}{y}[/tex] Where k' is another constant of proportionality. Now taking your example of current and resistance, you are indeed correct to say that current is inversely proportional to resistance because we can rewrite Ohm's law thus, [tex]I = \frac{V}{R}[/tex] So in this case, V is our constant of proportionality. Does that help to clear things up? 


#3
May2208, 03:01 AM

P: 206

Voltage is proportional to resistance. Voltage is proportional to current. 


#4
May2208, 03:10 AM

Emeritus
Sci Advisor
PF Gold
P: 9,772

Voltage, Current, Resistance Relationship



#5
May2208, 03:12 AM

P: 206

When a circuit shortcircuits, does that mean current is zero hence resistance is low?



#6
May2208, 03:19 AM

Emeritus
Sci Advisor
PF Gold
P: 9,772




#7
May2208, 03:21 AM

P: 206




#8
May2208, 03:25 AM

Emeritus
Sci Advisor
PF Gold
P: 9,772

The current is proportional to the voltage (which in this case is constant) and inversely proportional to the resistance, hence a low resistance results in a large current. 


#9
May2208, 03:35 AM

P: 206




#10
May2308, 03:59 AM

Emeritus
Sci Advisor
PF Gold
P: 9,772

It would perhaps be prudent to mention that the majority of shorts are not Ohmic conductors, since a very large current flows that short (wire) usually heats up very quickly and therefore there is a nonlinear relationship between V, R and I. 


Register to reply 
Related Discussions  
Current/Voltage relationship for a filament lamp?  Introductory Physics Homework  10  
Integrating CurrentVoltage Relationship for a Capacitor  Engineering, Comp Sci, & Technology Homework  1  
Voltage, Current, Resistance definitions  Electrical Engineering  4  
Current to voltage conterter and voltage to current converter  Engineering, Comp Sci, & Technology Homework  3  
Help  Amplifier Frequency Voltage relationship  Electrical Engineering  4 