Calculating Power Loss from Voltage Change at 3 Ohms Resistance

AI Thread Summary
To calculate power loss from voltage change at 3 ohms resistance, first determine the current at 12,000V using the formula P=IV, which results in a higher current and thus greater power loss. Next, calculate the current at 50,000V, which will be significantly lower, leading to reduced power loss. The power wasted can be calculated using the formula I^2R for both voltage scenarios. Finally, find the difference in power loss between the two voltage levels to assess the savings. This approach effectively demonstrates the impact of voltage on power loss in electrical systems.
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Homework Statement


a power station delivers 520kW of power to a factory through wires of total resistance of 3 ohms ,how much less power is wasted if the electricity is deliverd at 50,000V rather than 12,000V


Homework Equations


P=IV=I^R =V^/R


The Attempt at a Solution



I tried to use voltage and resistance to calculate power and compare that with 520kW ,but it did not make any sense.Please help me.
 
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Determine the current flowing at 12000 V and 520 kW. Power wasted I^2R. Next determine the current at 50000 V and 520 kW (it will be much less than earlier). Determine power wasted. Find the difference.
 
Thanks a lot .
 
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