Answer:305.52 s
Explanation:
Given
Resistance of conductor [tex]R=30 \Omega [/tex]
mass of water [tex]m=500 gm[/tex]
Initial Temperature [tex]T_i=30^{\circ}C[/tex]
Final Temperature [tex]T_f=100^{\circ}C[/tex]
specific heat [tex]c=4.19\times 10^3 J/kg-^{\circ}C[/tex]
Heat required to heat water [tex]Q=mc\Delta T[/tex]
[tex]Q=0.5\times 4.19\times 10^3\times (100-30)[/tex]
[tex]Q=146.65\times 10^3 J[/tex]
Heat generated by stove in time t
[tex]H=\frac{V^2}{R}\times t[/tex]
[tex]H=\frac{120^2}{30}\times t[/tex]
[tex]\frac{120^2}{30}\times t=146.65\times 10^3[/tex]
[tex]t=\frac{146.65\times 10^3\times 30}{120^2}[/tex]
[tex]t=305.52 s\approx 5.09 min[/tex]
