Question

A rigid container with thermally insulated walls contains a gas and a coil of resistance $50 \,\Omega$, carrying a current of $1 \,A$. The change in internal energy of the gas after $2$ minutes will be

• A. 6 kJ
• B. 10 kJ
• C. 3 kJ
• D. 12 kJ
• E. 1.5 kJ

Answer 1

Answer: (A)

The given
$R =50 \,\Omega $
$i =1\, A $
$t =2 \,\min =2 \times 60=120\, s $
We know that
$H =i^{2} R t $
$=(1)^{2} \times 50 \times 120 $
$=6000\, J $
Or$=6 \times 10^{3}=6 \,kJ$