32. An electric heater, with a resistance of 55 ohm, works with a current of 4 a passing through the heater. If it works for 300 seconds, the heat generated is____________________ Scorch

32. An electric heater, with a resistance of 55 ohm, works with a current of 4 a passing through the heater. If it works for 300 seconds, the heat generated is____________________ Scorch

Q=UIt=Iˇ2Rt=4ˇ2×55×300=264000J

An electric heater, 55 ohm resistance, working through the electric heater current is 4 A, then it works 300 seconds to produce heat is coke
There is another way
In order to solve the problem of electricity consumption for "agriculture, rural areas and farmers" (i.e. rural areas, farmers and agriculture), the state has carried out a large-scale rural power grid transformation, which makes the light bulbs in farmers' homes turn on and the motors in the villages work normally, The level of agriculture has been improved. One of the contents of this transformation is to replace the original thinner transmission line with a thicker one. Please analyze the reason why the light bulb in the farmer's home turns on

1. According to Joule's Law: q = I & sup2; RT = (4a) & sup2; · 55 Ω· 300s = 264000j
"Thinner transmission line replaced by thicker transmission line" actually reduces the resistance of the transmission line. For the same power supply, it is equivalent to reducing the voltage loss on the transmission line (equivalent circuit is that the resistance of the transmission line is in series with the resistance of the user's electrical appliance), that is, increasing the voltage at the user's end, so the light bulb in the farmer's home turns on

The resistance of an electric furnace is 48.4 Ω. How much work does the current do when it is connected to a 220 V circuit for 10 minutes

The problem is pure resistance circuit. That is to say, all work done by current is converted into heat energy. According to w = u ^ 2 / R * t, w = 220 * 220 / 48.4 * 10 * 60 = 6x10 ^ 5 J. (note, Joule unit)

The resistance of the heating wire of an electric kettle is 48.4 Ω. How much work does the current do when it is connected to a 220 V circuit and energized for 5 minutes?

p＝∪2/R=220x220/48.4=1000w
The fifth power of W = Pt = 1000x5x60 = 3x10
Formula and unit to sort out their own, not used to input