Final answer:
The statement that step-up transformers increase voltage and decrease amperage is true. Step-up transformers increase the voltage output and decrease current, in accordance with the transformer equation linking voltage ratios to the ratio of winding turns.
Step-by-step explanation:
True or False, Step up transformers increase voltage and decrease amperage? The statement is True. A step-up transformer is a device that transforms voltages from one value to another using the principle of electromagnetic induction. Specifically, it increases the voltage while simultaneously decreasing the current in an electrical circuit. This is based on the transformer equation, which shows that the ratio of the secondary to primary voltages in a transformer equals the ratio of the number of turns in their windings. For a step-up transformer, this ratio is greater than one. Conversely, a step-down transformer decreases voltage and increases current. The conservation of power in an ideal transformer, where the electrical power output equals the power input (Pp = IpVp = IsVs = Ps), explains why an increase in voltage leads to a decrease in current, and vice versa, assuming negligible resistance and high transformer efficiency, which often exceeds 99%.