Two coils have self-inductances L₁=8 mH and L₂=2 mH. Their currents increase at the same constant rate. At an instant the powers supplied are equal. If the corresponding quantities are I₁, V₁, W₁ and I₂, V₂, W₂, which relations may be true?
Select all that apply

Question

Two coils have self-inductances L₁=8 mH and L₂=2 mH. Their currents increase at the same constant rate. At an instant the powers supplied are equal. If the corresponding quantities are I₁, V₁, W₁ and I₂, V₂, W₂, which relations may be true?

Select all that apply

G1 Physics · Accepted Answer

Since dI/dt is the same, V∝L, so V₂/V₁=L₂/L₁=1/4. Equal power VI gives I₁/I₂=V₂/V₁=1/4. With W=1⁄2LI², W₁/W₂=4×(1/16)=1/4, so W₂/W₁=4. Hence A,C,D.

Two coils have self-inductances L₁=8 mH and L₂=2 mH. Their currents increase at the same constant rate. At an instant the powers supplied are equal. If the corresponding quantities are I₁,V₁,W₁ and I₂,V₂,W₂, which relations may be true?