yes, true
power = V i but V = i R
so
Power = i^2 R = V^2/R Joules per second or "Watts"
Energy (or heat) = Power * time
so indeed
H = i^2 R t = V^2/R Joules
Now how much heat do we need?
H = mass * specific heat * change in temp
H = 0.5 * 4.19*10^3 * 70 Joules
so in the end
(120^2/30) * t = 35 * 4.19*10^3
t is in seconds
Some stoves use the heat produced by current flowing through a conductor. If the heating element (conductor) has a resistance of 30 ohms, how long will the burner have to work to heat 500 g of 30°C water up to its boiling point? The specific heat of water is 4.19 x 103 J/kg·°C, and the household voltage is (120V).
I think I use this formula at some point:
H=I^2Rt
but that's really all I know about solving this, can someone please help??
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