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A current of 2 mA was passed through an unknown resistor which dissipated a power of 4.4 W. Dissipated power when an ideal power supply of 11 V is connected across it is

Asked in JEE Main 10th Jan 2nd Shift 2019 · Heating and power in resistors

• (1) 11×10⁻⁴ W
• (2) 11×10⁻⁵ W
• (3) 11×10⁵ W
• (4) 11×10⁻³ W

Step-by-step solution

Why the other options are wrong

• (1) Power-of-ten slip: squares 2×10⁻³ as 4×10⁻⁵, making R ten times too small.
• (3) This is the resistance value R=1.1×10⁶ Ω=11×10⁵, reported as if it were the power.
• (4) Treats 2 mA as 0.02 A, giving R=1.1×10⁴ Ω and a power 100 times too large.

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