Two resistance R1 and R2 when connected in series consume power 25W. When connected in parallel, they consume 100W. What is the ratio of the power of each?

Question

Two resistance R1 and R2 when connected in series consume power 25W. When connected in parallel, they consume 100W. What is the ratio of the power of each? (A) 1/4 (B) 1/3 (C) 1/2 (D) 1

Tardigrade Admin · Accepted Answer

Let W1 and W2 be the power of two resistances. Then, W1+W2=100 and (W1 W2/ W1 + W2)=25 ⇒ W1W2=2500 On solving, we get W1=W2=50. ∴ W1/W2=1

Q. Two resistance $R_{1}$ and $R_{2}$ when connected in series consume power $25 W .$ When connected in parallel, they consume $100 W .$ What is the ratio of the power of each?

$1/4$

$1/3$

$1/2$

$1$

Let $W_{1}$ and $W_{2}$ be the power of two resistances.
Then, $W_{1} + W_{2} = 100$ and $\frac{W _{1} W _{2}}{W _{1} + W _{2}} = 25$
$\Rightarrow W_{1} W_{2} = 2500$
On solving, we get $W_{1} = W_{2} = 50.$
$∴ W_{1} / W_{2} = 1$

Q. Two resistance R1​ and R2​ when connected in series consume power 25W. When connected in parallel, they consume 100W. What is the ratio of the power of each?

1/4

1/3

1/2

1

Let W1​ and W2​ be the power of two resistances. Then, W1​+W2​=100 and W1​+W2​W1​W2​​=25 ⇒W1​W2​=2500 On solving, we get W1​=W2​=50. ∴W1​/W2​=1

Q. Two resistance $R_{1}$ and $R_{2}$ when connected in series consume power $25 W .$ When connected in parallel, they consume $100 W .$ What is the ratio of the power of each?

$1/4$

$1/3$

$1/2$

$1$

Let $W_{1}$ and $W_{2}$ be the power of two resistances.
Then, $W_{1} + W_{2} = 100$ and $\frac{W _{1} W _{2}}{W _{1} + W _{2}} = 25$
$\Rightarrow W_{1} W_{2} = 2500$
On solving, we get $W_{1} = W_{2} = 50.$
$∴ W_{1} / W_{2} = 1$