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........$J.$
JEE MAIN 2022, Medium
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$H =i^{2} Rt$
$300=2^{2} \times R \times 15$
$\Rightarrow R =\frac{300}{60}=5 \Omega$
Now, for $i =3 A , t =10 s , R =5 \Omega$
$H =3^{2} \times 5 \times 10=450 \,J$
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