Question

solve my question give answer ⬇⬇⬇​

Answer 1

We know the Formula,

R = V²/P

Now, For First Lamp, V = 220 V, and P = 100 W.

∴ R₁ = 220²/100

∴ R₁ = 484 Ω

For Second Lamp, V = 220 V, P = 200 W,

∴ R₂ = 220²/200

∴ R₂ = 484/2

∴ R₂ = 242 Ω

(i) When they are connected in series,

R = R₁ + R₂ = 484 + 242

R = 726 Ω

Using Ohm's law,

V = IR

∴ 220 = I × 726

∴ I = 0.3030 A.

(ii) When they are connected in Parallel,

1/R = 1/R₁ + 1/R₂

∴ 1/R = 1/484 + 1/242

∴ R = 161.3 Ω

Again using the Ohm's law,

I = V/R = 220/161.3

I = 1.36 A.