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Question
A current of 0.8 A flows in a conductor of 40 Ω for 1 minute. The heat produced in the conductor will be ______.
Options
1445 J
1536 J
1569 J
1640 J
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Solution
A current of 0.8 A flows in a conductor of 40 Ω for 1 minute. The heat produced in the conductor will be 1536 J.
Explanation:
From Ohm's law, we know that
V = IR
Given: I = 0.8 A, R = 40 Ω, t = 1 min (60 sec)
Now, V = I.R
V = 0.8 × 40
V = 32 volt
Power, P = V × I
P = 32 × 0.8
P = 25.6 watt
Heat = P × t
Heat = 25.6 × 60
Heat = 1536 J
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