Physics, Chemistry and Biology: Post your doubts here!

[Mr.Physics]

Please help!
How much energy is converted in a resistor of 5 ohms carrying a current of 2 A for 10 s
A : 4j
b : 25j
c : 100j
d : 200j

R=5 ohm
I=2A

So find V
V=IR=2x5=10V

Now E=P x t
E =IxVxt
E=2x10x5=100J

The answer is C !!!!

 

[Bilal ashraf]

Thanks!!

 

[Bilal ashraf]

i suck at connecting equations together lol

 

[Mr.Physics]

Anymore ?????

 

[silver_moon]

Please help!
How much energy is converted in a resistor of 5 ohms carrying a current of 2 A for 10 s
A : 4j
b : 25j
c : 100j
d : 200j

the answer is D i think..coz
P=IV..so uv 2 find d voltage first...u do..V=RxI=2x5=10V

P=2X10=20W..so..E=PxT..so...2oWx10s=200j

 

[Mr.Physics]

may 2014 paper 1 ?

No problem. Just wait , u ll get it tomorrow

 

[Mr.Physics]

the answer is D i think..coz
P=IV..so uv 2 find d voltage first...u do..V=RxI=2x5=10V

P=2X10=20W..so..E=PxT..so...2oWx10s=200j

Yep sorry i used time 5 s

 

[Bilal ashraf]

so the answer is D not C ?

 

[Mr.Physics]

Yeah

 

[Bilal ashraf]

waaait a sec from where did u get the other 10?
look :
5 ohms
2 A
10 s
E = 10 x 2 x 5
= 100 J

 

[silver_moon]

so the answer is D not C ?

yeah!..u understood rit...hw???

 

[Bilal ashraf]

 

[silver_moon]

Yep sorry i used time 5 s

nxt tym be careful wn u reply 2 odrs..ny1 cn mk mistakes so its alrit!Mr.PHYSICS GENIUS!

 

[Bilal ashraf]

yeah!..u understood rit...hw???

no but i have a quiz on it tmw

 

[silver_moon]

View attachment 43097

which year ppr iz it???iz d ans B??

nxt tym be careful wn u reply 2 odrs..ny1 cn mk mistakes so its alrit![/q

 

[silver_moon]

no but i have a quiz on it tmw

seeriously??u din ndrstnd????u kno all d formulae byheart rit??so u hav 2 jz connect all d formulae n mk it one so dt u get d rit ans..if u din ndrstand dn re-read my ans again..u mit ndrstnd sth..

 

[Bilal ashraf]

which year ppr iz it???iz d ans B??

it isnt in any pastpapers i tried finding it ><

 

[Bilal ashraf]

seeriously??u din ndrstnd????u kno all d formulae byheart rit??so u hav 2 jz connect all d formulae n mk it one so dt u get d rit ans..if u din ndrstand dn re-read my ans again..u mit ndrstnd sth..

yeah i'm still memorizing it

 

[f.mohamed]

yeah i'm still memorizing it

Good Luck !

 

[ChubbyBunny]

yes ..u shud kno all kind ov logic gates:AND,OR,NOR,NOT.NAND!dts all-kno 2 drw dm coz dy smtime ask u 2 drw...n kno when in each gate the outputs will b high or low its very important..dont neglect it..go 2ru d rev.guide if u wnt..

Thank you very much.. Good luck for ur exams =)