(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

while surfing the internet i stumbled upon the following question:

Why ac(alternating current) is used to power houses instead of DC?

Answer:The answer lies in the transmission lines for the electricity. The wires have a defined resistance, and when current passes through them there is a power loss given by

W (power) = I (current) squared x R (resistance)

Clearly, lowering the current reduces the power loss considerably. The power transmitted is given by

W = V (voltage) x I, so we could multiply the voltage by 100, reduce the current by 100, transmit the same power, and reduce the loss in the wires by 10000. This high voltage is desperately unsafe in the domestic situation, so it must be reduced. Reducing DC is very difficult, so it is much easier to use AC.

2. Relevant equations

How can one lower the current without lowering the voltages and, at the same time,without changing the resistance of the wires?

**Physics Forums - The Fusion of Science and Community**

# Electricity- Power dissipation formula question

Know someone interested in this topic? Share a link to this question via email,
Google+,
Twitter, or
Facebook

- Similar discussions for: Electricity- Power dissipation formula question

Loading...

**Physics Forums - The Fusion of Science and Community**