Physics And Chemistry Help Available here

[Silent Hunter]

 

[xhizors]

sorry english man, now help me with this according to one equation V is directly proportional to I (V=IR) but according to another equation V is inversely proportional to I (P=IV)
how it is possible ??

 

[intelnehalem]

y=kx is for direct proportion where k is a constant
so substitute P=VI
P is directly proportional to I when V is a constant (parallel circuit )
P is directly proportional to V when I is a constant (series circuit)

 

[intelnehalem]

sorry english man, now help me with this according to one equation V is directly proportional to I (V=IR) but according to another equation V is inversely proportional to I (P=IV)
how it is possible ??

V=IR (resistance is constant so V is directly proportional with I)
in P=VI , power is changing depending on either of V or I, as I mentioned before if it is a series circuit then I is a constant and V can change so V is directly proportional to I and I is just a constant (coefficient) it is not inversely proportional I guess

 

[xhizors]

y=kx is for direct proportion where k is a constant
so substitute P=VI
P is directly proportional to I when V is a constant (parallel circuit )
P is directly proportional to V when I is a constant (series circuit)

i guess nopes if u r answering me ?? for parallel circuit or for series circuits V=IR will be followed (for metallic Conductors)

 

[intelnehalem]

To elaborate, P=I^2 x R since V=IR, substitute IR for V , from this i can't see any inverse proportion between V and I

These graphs show direct proportion for metallic conductors

 

[xhizors]

with my question I = Current and V for voltage (Practical Electricity) are u from Pakistan khi

 

[intelnehalem]

Nope I am from Sri Lanka that is why I asked you to write in English

 

[xhizors]

To elaborate, P=I^2 x R since V=IR, substitute IR for V , from this i can't see any inverse proportion between V and I

These graphs show direct proportion for metallic conductors

I is inversely proportional to V if P kept constant ( for P=IV )
first graph is for metallic conductors for what i was talking about , filament one is for thermistors.

 

[xhizors]

Nope I am from Sri Lanka that is why I asked you to write in English

hmm gr8 nice to talk to u and no problem well did u take computers

 

[intelnehalem]

To elaborate, P=I^2 x R since V=IR, substitute IR for V , from this i can't see any inverse proportion between V and I

These graphs show direct proportion for metallic conductors

I is inversely proportional to V if P kept constant ( for P=IV )
first graph is for metallic conductors for what i was talking about , filament one is for thermistors.

P can't be constant dude ! It depends on V and I
its like y=mx, y is never constant except for y=0,1,2,3... graphs but this is electricity we are talking about so both V and I gives P, if one of them decreases P also decreases !!
Power varies with V and I not the other way around!

 

[intelnehalem]

Nope I am from Sri Lanka that is why I asked you to write in English

hmm gr8 nice to talk to u and no problem well did u take computers

Nice to meet you too ! :beer: And yes, I am taking Computing this time I am going to do the Paper 3 (alternative to coursework btw)

 

[xhizors]

To elaborate, P=I^2 x R since V=IR, substitute IR for V , from this i can't see any inverse proportion between V and I

These graphs show direct proportion for metallic conductors

I is inversely proportional to V if P kept constant ( for P=IV )
first graph is for metallic conductors for what i was talking about , filament one is for thermistors.

P can't be constant dude ! It depends on V and I
its like y=mx, y is never constant except for y=0,1,2,3... graphs but this is electricity we are talking about so both V and I gives P, if one of them decreases P also decreases !!
Power varies with V and I not the other way around!

y power cant be kept constant, what is power ? the source the electrical energy P=IV is mainly applicable in transformers

heres ideal transformers complete application (Ns/Np)=(Es/Ep)=(Ip/Is)
N is number of coils in either primary or secondry

power can be kept constant if and due to it V is inversely propotional to I

 

[xhizors]

oh i did coursework and teacher gave me 48 dont knw about examiner Inshallah he will be more impressed and will award me 49 i did on asp.net and csharp

 

[intelnehalem]

y power cant be kept constant, what is power ? the source the electrical energy P=IV is mainly applicable in transformers

heres ideal transformers complete application (Ns/Np)=(Es/Ep)=(Ip/Is)
N is number of coils in either primary or secondry

power can be kept constant if and due to it V is inversely propotional to I

Oh yeah ! that is only in transformers though I totally forgot that ! Thanks dude
It is VpIp= VsIs right? so here VpIp is constant (therefore it can be thought as P since P=VI) so then you are right ! :beer:

 

[abcde]

@Any Genius: I am having difficulty in the N03 theory question regarding LDR and Logic gates... Its 1 comeplete questions and i wud be really glad if sum1 cud thoroughly solve it and xplain... nd 1 more thing are red spot answers reliable????????

Usman,is this the paper you're referring to? http://www.xtremepapers.me/CIE/Cambridg ... 3_qp_2.pdf
I didn't find any question on LDR and logic gates here! Please point it out and I'll try my best to help you.
And Red Spot answers are not very reliable so prepare from the mark schemes instead.
Wish you all the best!

 

[xhizors]

Oh yeah ! that is only in transformers though I totally forgot that ! Thanks dude
It is VpIp= VsIs right? so here VpIp is constant (therefore it can be thought as P since P=VI) so then you are right ! :beer:

no problem well i m seeing this equation first time and apart from transformer this equation is really very usable when transmitting electricity through long wires, when power kept constant volts can be increased to reduce current which causes less loss of energy into heat ( also lower the chances of burning wires ) but question still remain y sometime I is directly proportional to V acc to V=IR but inversely acc to P=IV :Search:

 

[abcde]

Oh yeah ! that is only in transformers though I totally forgot that ! Thanks dude
It is VpIp= VsIs right? so here VpIp is constant (therefore it can be thought as P since P=VI) so then you are right ! :beer:

no problem well i m seeing this equation first time and apart from transformer this equation is really very usable when transmitting electricity through long wires, when power kept constant volts can be increased to reduce current which causes less loss of energy into heat ( also lower the chances of burning wires ) but question still remain y sometime I is directly proportional to V acc to V=IR but inversely acc to P=IV :Search:

Well that depends on whether the questions asks about resistance or power. You can answer accordingly then!

 

[xhizors]

really without resistance dhamaka hojata hai which we also call short circuit

 

[Usman17]

@Any Genius: I am having difficulty in the N03 theory question regarding LDR and Logic gates... Its 1 comeplete questions and i wud be really glad if sum1 cud thoroughly solve it and xplain... nd 1 more thing are red spot answers reliable????????

Usman,is this the paper you're referring to? http://www.xtremepapers.me/CIE/Cambridg ... 3_qp_2.pdf
I didn't find any question on LDR and logic gates here! Please point it out and I'll try my best to help you.
And Red Spot answers are not very reliable so prepare from the mark schemes instead.
Wish you all the best!

OH MY GODDDDDDDDDDD!!! :| THAT QUESTIONS ISNT THERE :S :S :S How the hell?????? :%)
But it is in the redspots :S Totally confused... Can u please see the question in the redspot? It is D03/p2/Q9...!!