Physics - Current Electricity Question with Solution | TestHub

In series,

$P_s=\frac{P_1 \times P_2}{P_1+P_2}=12 \mathrm{W}$

In parallel,$P_p=P_1+P_2=50 \mathrm{W}$

$\therefore P_1{P}_2=12\times 50=600$

Now,${\left(P_1-P_2\right)}^2={\left(P_1+P_2\right)}^2-4P_1{P}_2$

$={\left(50\right)}^2-4\times 600$

$=2500-2400=100$

$\therefore P_1-P_2=10$

Or$P_1=30 \mathrm{W}, P_2=20 \mathrm{W}$

$\therefore \frac{P_1}{P_2}=\frac{3}{2}$