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CBSE Class 12 · 2023 · Current ElectricityMultiple Choice

A current of

0.8 A

flows in a conductor of

40 Ω

for 1 minute. The heat produced in the conductor will be:

(A) $1445 J$
(B) $1536 J$ ✓ Correct
(C) $1569 J$
(D) $1640 J$

Answer: (B)

Solution

Joule heating:

H = I^{2} R t = (0.8)^{2} \times 40 \times 60 = 0.64 \times 40 \times 60 = 1536 J .

CBSE Class 12 Board · 2023 · Single correct option

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