Chapter 37, Problem 59A

Neon signs require about 12,000 V for their operation. What should be the ratio of the number of loops in the secondary to the number of loops in the primary for d neon-sign transformer that operates off 120-V lines?

To determine

To calculate: the ratio of the number of loops

Answer to Problem 59A

The ratio is $1:100.$

Explanation of Solution

Given:

Voltage in the secondary line $\left(V_2\right)=120V$

Voltage in the primary line $\left(V_1\right)=12000V$

Formula used:

  $\frac{V_2}{V_1}=\frac{N_2}{N_1}$

Calculation:

The relation between voltage and number on turns on primary and secondary winding is,

  $\frac{V_2}{V_1}=\frac{N_2}{N_1}$

  $\begin{array}{l}\frac{120V}{12000V}=\frac{N_2}{N_1}\\ \frac{N_2}{N_1}=\frac{1}{100}\\ \frac{N_2}{N_1}=1:100\end{array}$

The ratio of number of lines on secondary to primary is $1:100.$

Conclusion:  The ratio is $1:100.$