Analyse applications of step-up and step-down transformers
- The loss of energy due to heating up of energy is : H = I2Rt, where
- I is current in wire,
- R is resistance of wire
- and t is time of current flow
- Thus power loss is P = I2R
- Power loss can be reduced by reducing current or resistance.
- Since
, over long distance, due to extremely high values of l, the total resistance of the wire becomes very high and is hard to reduce. - We can reduce power loss by reducing current.
- We use the Step-Up transformers to increase the voltage many times using Ns>Np.
, so Vs>Vp
, So when Ns>Np , the current Is < Ip- Thus with higher voltage being transmitted , the current is reduced
- Thus power loss is also reduced.
- Then a step-down transformer is used near households to reduce the voltage to usable amounts.
, over long distance, due to extremely high values of l, the total resistance of the wire becomes very high and is hard to reduce.
, so Vs>Vp
, So when Ns>Np , the current Is < IpExtract from Physics Stage 6 Syllabus © 2017 NSW Education Standards Authority (NESA)