JEE Mains · Physics · STD 12 - 3. current electricity
A resistor develops \(300 \,J\) of thermal energy in \(15 \,s\), when a current of \(2\, A\) is passed through it. If the current increases to \(3 \,A\), the energy developed in \(10\,\,s\) is........\(J.\)
- A \(480\)
- B \(450\)
- C \(490\)
- D \(45\)
Answer & Solution
Correct Answer
(B) \(450\)
Step-by-step Solution
Detailed explanation
\(H =i^{2} Rt\) \(300=2^{2} \times R \times 15\) \(\Rightarrow R =\frac{300}{60}=5 \Omega\) Now, for \(i =3 A , t =10 s , R =5 \Omega\) \(H =3^{2} \times 5 \times 10=450 \,J\)
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