A) 10
B) 20
C) 80
D) 200
Correct Answer: B
Solution :
According to Joule's law, rate of production of heat (H) is given by, \[H={{i}^{2}}Rt.\] Where i is current flowing in the conductor, R, the resistance and t the time. Here : \[H=80J,\text{ }i=2A,\text{ }t=10s.\] \[80={{(2)}^{2}}\times R\times 10\] \[\Rightarrow \] \[R=\frac{80}{4\times 10}=2\Omega \] Note: Joule's law is associated with ohm's law. Whenever ohm's law holds. Joule's law also holds.You need to login to perform this action.
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