Power ratio calculated using P = I²R

Steps:

• Compute P_X = (0.50 A)² × 9 Ω = 0.25 × 9 = 2.25 W
• Compute P_Y = (3.0 A)² × 1.2 Ω = 9 × 1.2 = 10.8 W
• Ratio P_X / P_Y = 2.25 / 10.8 ≈ 0.208
• Round to nearest choice: 0.22

Why A is correct:

• 0.208 ≈ 0.22 exactly matches the calculated ratio from the power formula P = I²R.

Why the others are wrong:

• B: 0.75 from incorrect V = IR ratio (4.5 V / 6 V = 0.75)
• C: 1.3 approximates inverse ratio P_Y / P_X ≈ 4.8, not asked
• D: 4.5 from resistance ratio R_X / R_Y = 9 / 1.2, ignores current

Final answer: A