Transformers
Step-up transformers increase voltage.
Step-down transformers decrease voltage.
Simple Diagram:
secondary coil
Put your results into this table:
Number of Turns
Secondary
Primary Coil
Coil
Voltage
Input
Output
Step-up or
Step-down?
 In the National Grid, step-up transformers are used to increase the
voltage in power lines to 400,000V.
 This decreases the current (amps).
 This means the wires don’t get as hot, so less energy is wasted (less
electrical energy is transferred to heat energy).
 Step-down transformers are used to convert the voltage back to 230V,
which is what we have in homes.