CAPE Physics Unit 2 · 2009 · Paper 1 · Question Q18

Why is it advantageous to use an alternating current instead of a steady d.c. when transmitting electrical energy at high voltages?

1. (A)Transformers can be used to step down the voltage for use by the consumer.
2. (B)There is less electro-magnetic radiation from the cables.
3. (C)Less energy is lost with the a.c. of a particular r.m.s. value than the same value of d.c.
4. (D)Appliances in houses and factories can only work on alternating current.