Question

a resistor r and another resistor 2R are connected in parallel across a battery if heat is produced at a rate of 10 w in r then in 2R its produced at a rate of
40 W
20 W
10 W
5 W

Answer 1

@rock_mit182
@robtobey

Answer 2

@ganeshie8

Answer 3

@hartnn

Answer 4

\[P=\frac{ V^2 }{R }\]
determine the voltage, then use this expression to calculate the power dissipated by resistance 2R. Because they're connected in parallel they have the same voltage across their terminals

Answer 5

why is it V^2

Answer 6

i thought P = IV

Answer 7

yea I got it now

Answer 8

element law for resistor :\[V=IR \Rightarrow I=\frac{ V }{ R }\]

Answer 9

ok so since we have same voltage then if R is doubled then the P will be half
so the answer is 5 W?

Answer 10

yes, that's correct answer

Answer 11

ok thnx man
I have some more can you help me out

Answer 12

yes, you can post them