The charge supplied by source varies with time $'t'$ as $Q = at -bt^2$. The total heat produced in the resistor $2R$ before current reduces to zero
  • A$\frac{{{a^3}R}}{{6b}}$
  • B$\frac{{{a^3}R}}{{27b}}$
  • C$\frac{{{a^3}R}}{{3b}}$
  • D
    None of these
Diffcult
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