Need help with dotpoint 4.1.4 (1 Viewer)

[imoO]

Hi guys,

I need help with the dotpoint
Explain why voltage transformations are related to conservation of energy

I do not think we covered this in class, so any help would be appreciated.

Cheers

 

[youngminii]

When a transformer changes the voltage of electricity, it abides by the formula P = VI and so to abide by the conservation of energy, the current is also changed in the opposite magnitude. This allows the input power to equal the output power because of the conservation of energy. However, in practical transformers the output power is ALWAYS less than the input power. This is due to the loss of energy as heat because of the production of eddy currents within the transformer.

 

[meggo-meggo]

yeah, pretty much that you cannot get out more energy (power) from a transformer than you put in (principle of conservation of energy - energy cannot be created)
P=VI

Is/Ip = Np/Ns
so basically, this means that there is a loss in current with a greater number of coils. (or vice versa, increase in current with lesser number of coils). ideally, this means that the power output = power input.

in other words, if power stays the same and voltage increases (step up transformer), then current increases, and vice versa.

but due to dissipation of energy into thermal energy, output power is always smaller than input power