Current Electricity Part 2

Given that, initial current, I1=4A
Final current, I2=2I1=8A
Initial heat dissipated, H1=192J
Initial time, t1=1s
Final time, t2=5s
Let final heat dissipated = H2
By Joule’s law of heating,
H∝I2‌RT
Since resistance remains same at initial and final condition,
∴

H2

H1

=

I22Rt2

I12Rt1

=

I22t2

I12t1

Substituting the given values, we get

H2

192

=(

8

4

)2×

5

1

⇒H2 = 3840 J