A power station makes a fixed amount of power and sends it down a long cable to a town. The cable has resistance, so some energy is wasted heating it. A step-up transformer raises the voltage for the journey, which (because the power stays the same) lowers the current, and a smaller current wastes far less energy. Raise the voltage to bring the wasted power below the target.
MissionKeep the power wasted in the cable below 1600 W.Round 1Streak 0Best 0
Raising the voltage will make the wasted power:
The station sends 100 kW. The current keeps flowing on its own. Set the voltage, predict, then measure.
transmission current I = P ÷ V20 A
power wasted = I² × R?
power delivered to the town?
VₚIₚ = VₛIₛ, so raising the voltage lowers the current. Cable resistance R = 4 Ω.