A television picture tube requires a high potential difference

which in older models is provided by a step-up transformer. The transformer has 18 turns in its primary and 2458 turns in its secondary. A potential difference of 112 V is placed across the primary.
What is the output potential difference?
Answer in units of V

It is a simple turns ratio to voltage ratio:

112 volts input to the primary winding of 18 turns.

2,458 turns in the secondary windings; thus, 2,458 / 18 = about 137

then 137 x 112 volts = 15,344 volts to the CRT anode.

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